The Ferritic Solution - Euro Inox

International Stainless Steel Forum (ISSF)Founded in 1996, the International Stainless Steel Forum (ISSF) is a non-profitresearch organisation that serves as the world forum on various aspects of theinternational stainless steel industry. Whilst having its own Board of Directors,budgets and Secretary General, ISSF is part of the International Iron and SteelInstitute (IISI). ISSF now comprises some 67 company and affiliated membersin 24 countries. Jointly, they are responsible for around 85 percent of worldwidestainless steel production. A full list of members can be found on the ISSFwebsite: www.worldstainless.org.

ContentsSummary “The Ferritic Solution” by Jean-Yves Gilet 5Foreword: “A steel whose time has come” by ICDA 6What they’re saying about ferritics 9The “fabulous ferritics” 13Corrosion resistance properties 21Mechanical and physical properties 27Forming ferritic grades 31Joining ferritic grades 37Products and applications 45Appendices:The chemical composition of ferritic stainless steels 59Surface finishes 63References 64ISSF membership 66Acknowledgements 67

Structural steelwork forhighway bridge in Durban,South Africa, of paintedferritic stainless steel.

Summary“THE FERRITIC SOLUTION”By Jean-Yves Gilet, Chairman of the ISSF Market Development Committee (MDC)ISSF first discussed a project to promote ferritic grades inFebruary 2004, many members having pointed out that nojoint industry effort was being made in this direction.Under the guidance of the Market DevelopmentCommittee, an international group of experts, led by PhilippeRichard, started by gathering market statistics on ferriticgrades and applications. They received contributions fromall around the world – especially Japan, where the ferriticsmarket is the most developed.The ICDA soon proposed to join the initiative and cofundthe project. This we accepted with great pleasure, asa concrete example of cooperation between internationalbusiness organisations.During the project’s start-up phase, nickel prices hitthe roof and interest in more price-stable grades increaseddramatically. ISSF then gave the project highest priority!I am now proud to present the results, which will ‘hit themarket’ at just the right time.I strongly believe that ferritic stainless steels can andshould be much more widely used. The purpose of thispublication is to bring about more extensive use of thesegrades.Stainless steels are ‘stainless’ because their chromiumcontent gives them remarkable resistance to corrosion.Ferritic grades, containing only chromium and possiblyother elements (Mo, Ti, Nb, etc.), are no exception. Wellknownstandard ferritic grades 409, 410 and 430 are readilyavailable all over the world. Very successfully used inimportant applications, such as washing-machine drumsand exhaust systems, they actually have much broaderapplication potential, in numerous fields.More recently-developed ferritic grades, such as 439and 441 meet an even broader range of requirements. Theycan be formed to more complex shapes and joined usingmost conventional joining methods, including welding.Thanks to the addition of molybdenum, the resistance offerritic grade 444 to localised corrosion is at least equal tothat of austenitic grade 316.Since ferritic grades do not contain nickel, their cost islower and more stable than that of austenitic stainlesssteels. They can therefore:• complement type 304 within the stainless steel family(although 304 remains a versatile and commonly usedgrade);• be an alternative to the 200 series (offering generallybetter usage properties);• substitute for other materials in many areas (e.g. carbonsteel, Cu, Zn, Al, plastic, etc.), thanks to their specialtechnical properties – the drivers for replacement being,usually, technical and Life Cycle Cost benefits.Ferritic stainless steels’ magnetism is not a ‘negative’quality, somehow associating it with ordinary carbon steel.On the contrary, magnetism is a special asset of theseexcellent stainless steels, marking them out from otherstainless steel grades.To get the best results from ferritics, it is essential that:• new users be trained in forming and joining techniques;• the user consult his stainless steel producer regardingcorrect grade selection;• the user acquire his material from a reliable source,able to offer proven guarantees as to the grade, qualityand origin of the material supplied.The high quality of the team’s efforts and the strong supportof the ICDA allow us today to present a reference documentfor our stainless steel business. It benefits from highlyinteresting testimonials from customers, showing a livelyinterest in new developments. ISSF is grateful for all thesecontributions.Jean-Yves GiletChairmanMarket Development CommitteeISSF

Foreword“A steel whose time has come”by Friedrich Teroerde of the International Chromium Development AssociationI must first thank ISSF for inviting the ICDA to write theforeword to The Ferritic Solution – a publication that isinevitably eloquent on the subject of chromium.The ICDA was set up in Paris, in 1990, and currentlyboasts some 96 Members from 26 countries across 5continents. Our mission is to tell the world the positivestory of chromium.Chromium is used in iron and steel to produce stainlesssteel and other alloys. In stainless steel, chromium is aspecial ingredient. It is the alloying element that makesstainless steel “stainless”, giving it its remarkable corrosionand oxidation resistance. Chromium is both readily availableand easily recycled in its stainless steel form, posing nothreat to the environment.As a body representing the chromium producers, we aresponsoring this handbook because we believe it will developthe chromium industry. Chromium is never used alone.The Market Development Committee of ICDA has thereforebeen implementing projects of common interest with sisterorganisations like ISSF for some years. Chromium is thebasic element of all families of stainless steel – at an averagecontent level of 18 percent. The annual consumption ofstainless steel is increasing at a compound growth rate of 5percent and the material is used in an increasing number ofapplications in the food, beverage, mining and automotiveindustries and in architecture.You will be aware that nickel, used in “austenitic”stainless steels is subject to considerable price fluctuations,due to stock market factors. In fact, in the last few years, thenickel price has increased to unprecedented levels, greatlyaffecting the cost of austenitic grades.Ferritics, the second great family of stainless steels,contain no nickel. They do, however, contain chromium. Inthe context of our own development, given the exceptionalgrowth in the stainless steel market, we feel we shouldstrongly encourage the broader use of ferritic grades, atthis time.We were therefore delighted when ISSF asked us to supportits project to identify and develop new ferritic marketapplications. The admirable aim of this project is to achievesustainable growth in the stainless steel market and builda bright future for these excellent grades.Looking at information already available on ferriticgrades, one finds plenty of material on stainless steel ingeneral but little dedicated specifically to ferritics – althoughsuch grades have existed for almost 100 years! This lackhas encouraged ISSF to create the current handbook. Itprovides essential information on the technical properties,advantages and potential applications of ferritic gradesand gives fabrication recommendations. It also attempts tocorrect certain popular misconceptions regarding the useand characteristics of ferritic stainless steels.In conclusion, ICDA is aware that the volatility of nickelpresents a major problem for stainless steel users. Weare keen to support the industry and its customers byparticipating in the search for alternative solutions. It isclear to us that, thanks to its proven technical qualities andcost advantages, ferritic stainless steel is a steel whosetime has come.The following pages will guide existing and potentialstainless steel users in extending the use of ferritic gradesinto new and exciting application areas.Friedrich TeroerdeChairmanMarket Development CommitteeICDA

The shining appearanceof ferritic is a symbolof cleanliness andhygiene in food-contactapplications.

What they’re saying about ferriticsThe economic advantages and technical merits of ferritic grades have beenappreciated by certain market sectors for a number of years. The followingtestimonials, representing both existing and evolving markets, show that thesebenefits are becoming more widely understood.Stefan RaabDirector Corporate Purchasing of Product Materials,BSH Bosch und Siemens Hausgerate Gmbh, Munich, Germany“We use stainless steel in about a third ofour products. Our reason for using thismaterial is partly functional, becauseof its corrosion resistance, and partlyaesthetic. The share of ferritic stainlesssteel is approximately 50 percent at thistime. Our intention is to increase this,mainly because ferritic gives the customer the benefits ofstainless steel in terms of functional qualities and design, inmany application areas, but within a limited cost frame. Wewill use ferritic grades wherever corrosion resistance andformability allow.”Roberta BernasconiManager, Global Technology – Materials,Whirlpool Corporation, Cassinetta di Biandronno, Italy“As a manufacturer of home appliances,we use ferritics for our refrigerators andwashing machines and are evaluatingconversion to ferritics for cookingappliances and dishwashers. The costadvantage is such that it makes sensefor us and our customers that we shouldmake more use of these grades.“We accordingly design our products with the necessarymanufacturing considerations in mind and occasionally selecta coated grade and even a fingerprint-protected coated grade,if need be, to ensure long service life. We may, on occasion,use a higher-alloyed ferritic grade. The important thing is tobenefit from the economic advantages of using ferritics.“We find them excellent for our applications and, giventhe high cost of nickel, the future, in our case, definitely lieswith these excellent steels.”Jean-Louis LalbaMarket Buyer for Groupe SEB, (Tefal, Rowenta, Krups,Moulinex, Arno, All Clad, Panex, etc.), Rumilly, France“We use about 15,000 metric tons ofstainless a year, of which some 40percent is ferritic. Our group originallyused ferritics for cookware lids, forwhich they are ideal, for the stamped orbrazed bases of induction cookware andfor oven housings. This has extendedto include frying pans, in those cases where the result isentirely satisfactory for the end-user.“Often, in such applications, the corrosion resistance,deep drawing and polishing characteristics of ferriticshave proved very acceptable both for us and our customers.There are cases where very demanding manufacturing orin-service requirements will exceed the limits of ferriticgrades, in terms of one or more of these qualities or interms of ease of processing. And there is even irrationalprejudice against ferritics in some countries! However, wefind these grades to be a perfect choice in many instances.Indeed, their magnetic nature is essential to stainless steelinduction cookware. And, of course, the price of ferritics isstable and reliable.“Given our good experience of ferritics, we intend toextend their use to other applications.”

In the sugar industry,ferritic stainless steelhas proved superiorto carbon steelon every level.10

Gaetano RonchiSenior Manager, Metals Procurement, IKEA“We use stainless steel for pots & pans,cutlery – including knives – and bathroomand kitchen accessories. Our currentannual consumption, of 60,000 tons ayear, is growing by about 15 percent ayear. A substantial part of this is ferritic.“In mid-2003, IKEA decided to adopt ferritic gradesas general-purpose stainless steels, largely due to thematerial’s stable, predictable price. Tests showed thatarticles with welded seams require a grade with higherchrome content than standard 430 for optimum corrosionresistance and that welded components need furtherprocessing to meet requirements. However, the decisionrepresented a breakthrough for our development of stainlesssteel articles. Our sales growth and the use of stainlesssteel in new-product design would have been seriouslyjeopardised had we stayed with austenitic grades.“A significant number of IKEA’s stainless steel articlesare manufactured by an Asian OEM and the success ofour transition to ferritics has been due to educating andtraining the Group’s purchase offices in Asia and its OEMsubcontractors. Our target is to phase out austenitic gradescompletely, replacing them with upgraded ferritics. We arecurrently testing new ferritic grades with enhanced deepdrawingor corrosion-resistance properties.”Michael LeungAssistant Manager,Yiu Heng International Company Limited, Macao“The main products of our subsidiaryXinhui RiXing Stainless Steel Products,based in Guangdong Province, China,are stainless steel cookware and kitchenutensils. At the time of writing, thecompany consumes about 800 metrictons of stainless steel per month, of which 66-70 percent isferritic. When we launched our factory, in 1999, we just used400-series grades on the bottom of cookware. We beganusing them for cookware bodies in 2002.“Low cost is not the only reason for favouring ferritics. Ferriticgrades are magnetic and have good thermal conductivity. Theyare easy to recycle, which helps save the planet’s resources.Changing from 304 to ferritic means that the manufacturerbecomes more competitive and the consumer gets a safeproduct at a lower price. We must correct the unfoundedprejudice that because ferritics are magnetic they are lowqualityand have poor corrosion resistance.“In factories where 304 is predominantly used, changing toferritic grades means adjusting the manufacturing processand dies. This is costly. Our experience, however, shows thattotal production costs can be lowered with ferritics.“Overall, we are very satisfied with ferritics. A good rangeof ferritic grades has been developed, to meet a wide varietyof requirements. We hope ferritic stainless steel becomeswidely available in steel service centres and becomes moreextensively used in a broad range of sectors.”Atushi OkamotoManager of No.1 Production Section, Osaka works,Takara Standard Corp., Japan“Takara Standard is a major Japanesemanufacturer of kitchen and bathroomproducts. We use stainless steel for sinksand top panels of built-in kitchens andfor bathtubs and mounting componentsof built-in baths. This company has usedferritic grades for about 40 years, for the simple reason thattheir properties are sufficient for these applications.“We are successful with ferritics because our productdesign takes into account the specific mechanical propertiesof these grades and we have appropriate press-forming anddie technology. We have met no major problems with ferriticgrades. When an intricate shape is required, we carry outtrials, to establish the best processing parameters.“To conclude, we are very satisfied with ferritic stainlesssteels. I would like to see guidelines issued to help companieschoose the right ferritic grade for their application.”Other testimonials follow onthe left-hand pages before each chapter...11

The “fabulous ferritics”In the face of an explosion in raw-material costs, ferritic stainless steels areemerging as a useful solution in many applications where cost-saving materialsubstitution has become an imperative.In recent years, prices of raw materials such as aluminium,copper, zinc and nickel have exploded. Stainless steelproducers and users, notably, are greatly affected by thehigh and volatile nickel price – which fluctuates daily. Nickelis a constituent of the widely used “austenitic” (300-series)stainless steel grades.Lower cost, stable priceThe good news is that ferritic (400-series) stainless steelgrades – low and stable in price yet boasting impressivetechnical characteristics – are waiting in the wings, ready toprove an excellent alternative material for many supposedly“austenitic-only” applications.50,00048,00046,00044,00042,00040,00038,00036,00034,00032,00030,00028,00026,00024,00022,00020,00018,00016,00014,00012,00010,0008,0006,0004,0002,0000LME CASH NiCkEL PriCE 1999-2007 (US $/T)00 00 00 00 00 00 01 01 02 02 02 03 03 04 04 04 05 05 05 05 06 07 07Stainless steel producers have no control over thesephenomena, whose inevitable effect is to both push up anddestabilize the cost of their nickel-containing grades. Thissituation is forcing some existing users of these grades toseek materials that cost less than austenitics but whichmight still provide fabrication and in-service characteristicsadequate for their product or application.The situation can also scare off potential users of stainlesssteel, who may believe that stainless steels possessing thequalities they need are financially out of reach.Containing no nickel, ferritic grades basically consist of ironand chromium (min. 10.5%). The price of chromium – theingredient that makes “stainless” steel especially corrosionresistant – is historically relatively stable. Certain ferriticgrades contain additional alloying elements, such asmolybdenum, to enhance specific properties.Ferritic stainless steels share most of the mechanicaland corrosion-resistance properties of their moreexpensive cousins, the austenitics, and even improve onaustenitics in certain characteristics. Why pay for nickel ifyou don’t have to?Users of copper, aluminiumor austenitic stainless steels insearch of another solution cantake heart. Ferritics are often anaffordable and technically idealway to benefit fully from stainlesssteel’s unique qualities.Professional griddle, in grade 430.“Why pay for nickelif you don’t have to?”Canopy, in grade 446M, S. Korea.13

The 5 ferritic “families”Ferritic grades fall into five groups – three families ofstandard grades and two of “special” grades. By far thegreatest current use of ferritics, both in terms of tonnageand number of applications, centres around the standardgrades. Standard ferritic stainless steels are plainly,therefore, totally satisfactory and entirely appropriate formany demanding applications.sTANdArd ferrITIC grAdes91% of total volume in 2006Group 1 Group 2 Group 310%-14% 14%-18%Types 409, 410, 420Cr content: 10%-14%Type 430Cr content: 14%-18%Group 1 (type 409/410L) has the lowest chromium contentof all stainless steels and is also the least expensive. Thisgroup can be ideal for non- or lightly-corrosive environmentsor applications speCIAl where slight ferrITIC localised grAdes rust is acceptable.Type 409 was originally 9% of designed volume in 2006 for automotive exhaustsystemsilencers Group (exterior 4 parts Group in non-severe 5 corrosiveenvironments). Type 410L is often used for containers, busesand coaches and, recently, LCD monitor frames.14%-18%stabilised30% 48% 13%Added MoOthers7% 2%Types 430Ti, 439, 441, etc.Cr content: 14%-18%.Include stabilising elementssuch as Ti, Nb, etc.Group 2 (type 430) is the most widely used family offerritic alloys. Having a higher chromium content, Group2 grades show greater resistance to corrosion and behavemost like austenitic grade 304. In some applications, thesegrades are suitable to replace type 304 and are usually ofhigh enough grade for indoor applications. Typical usessTANdArd ferrITIC grAdesinclude washing-machine 91% of total drums, volume in indoor 2006 panels, etc. Type430 isGroupoften substituted1forGrouptype2304 in householdGrouputensils,3dishwashers, pots and pans. For information on its weldingcharacteristics, see p. 38.10%-14% 14%-18%Group 30% 3 includes types 430Ti, 48% 439, 441, etc. 13% Comparedwith Group 2, these grades show better weldability andformability. Their behaviour is even, in most cases, betterthan that of 304 austenitic grades. Typical applicationsTypes 409, 410, 420Cr content: 10%-14%include sinks, exchanger tubes (the sugar industry, energy,etc.), exhaust systems (longer life than with type 409) andthe welded parts of washing machines. Group 3 grades caneven replace type 304 in applications where this grade is anover-specification.Type 430Cr content: 14%-18%14%-18%stabilisedTypes 430Ti, 439, 441, etc.Cr content: 14%-18%.Include stabilising elementssuch as Ti, Nb, etc.Containers, in grades 409L and 410L.Types 434, 436, 444, etc.Mo content above 0.5%Cr content: 18%-30%or not belongingto the other groupsspeCIAl ferrITIC grAdes9% of volume in 2006Group 4 Group 5“Standard ferritic stainless steelsare totally satisfactory andentirely appropriate for manydemanding applications.”Added MoTypes 434, 436, 444, etc.Mo content above 0.5%Others7% 2%Cr content: 18%-30%or not belongingto the other groups14The 5 grOups Of ferrITIC grAdes

Group 4 includes types 434, 436, 444, etc. These gradeshave added molybdenum, for extra corrosion resistance.Typical applications include hot water tanks, solar waterheaters, visible parts of exhaust systems, electrical-kettleand microwave oven elements, automotive trim and outdoorpanels, etc. Type 444’s corrosion-resistance level can besimilar to that of type 316.Group 5 (types 446, 445/447 etc.) has additionalchromium and contains molybdenum, for extra corrosionand scaling (oxidation) resistance. This grade is superiorto type 316 in respect of these properties. Typical usesinclude applications in coastal and other highly corrosiveenvironments. The corrosion resistance of JIS 447 is equalto that of titanium metal.Impressive referencesAmong the success stories of ferritic stainless steels, twotypical and extremely demanding applications stand out.For years, ferritic grades have been very extensively used intwo extremely demanding applications: automotive exhaustsystems and washing-machine drums.Exhaust systems are exposed to high temperatures andcorrosive environmental conditions. The use of stainlesssteel (ferritic) makes it possible to extend the warrantyperiod of these parts.Washing-machine drums have to withstand detergentsand a virtually constantly humid environment. In this context,however, localised corrosion would be utterly inadmissible.Car owners and householders will readily testify to theirsatisfaction with the long life of their washing machinesdrums and exhaust systems. For manufacturers of theseproducts, “fabrication friendliness” and major economicadvantages are additional factors making ferritic stainlesssteel the obvious choice.“…in many cases, ferritics areemerging as a better choice thanmore expensive materials.”Other current uses of ferritic grades range from kitchenwareand catering equipment to indoor furniture and decorativeitems, automotivetrim, superheater andreheater tubes, burners,air-conditioning ducts,barbecue grills, etc.Many new applicationsare waiting to emerge.Today’s excellent ferriticsTop-quality ferritic stainless steels have existed for someyears now and much intensive research and developmenthas gone into defining the remarkable grades currentlyavailable.They are neither new to the market nor to their highlyexperiencedproducers. Strangely, though, attitudes tothese steels seem tinged with misconception and ignorance,for largely historical reasons. Grade 430 was once the onlygrade available and early, pioneering users may havereceived insufficient technical support regarding the useof this grade – especially, perhaps, in the case of weldedstructures or more corrosive conditions. In any event, thefalse idea took hold, in some quarters, that ferritics are“inferior” and that only austenitics will do.Ferritics moved ona long time ago! Fulltechnical support isavailable today and therange of grades hasgreatly increased anddiversified, to meetusers’ needs, in termsof properties. Sincethese properties arebroadly comparable to those of austenitics, it is wrong tosee ferritic grades as either inferior or superior. They arejust different – and usefully so.Overpass noise-absorbing plate, Japan. Solar water heater, Taiwan.15

Ferritic special trump cards• Ferritics are magnetic.• Ferritics have low thermal expansion(they expand less than austenitics when heated).• Ferritics have excellent high-temperatureoxidation resistance (they are less prone toscaling than austenitics).• Ferritics have high thermal conductivity(they conduct heat more evenly than austenitics).• Ferritics stabilised with niobium have excellentcreep resistance (they deform less thanaustenitics in response to long-term stresses).• Ferritics are easier to cut and workthan austenitics (which require specialtools and more powerful machines andgenerate greater tooling wear).• Ferritics are significantly less prone tospringback than austenitics, during cold forming.• Ferritics have higher yield strength(similar to that of popular carbon steels)than type 304 austenitics.• Ferritics, unlike austenitics, are not proneto stress corrosion cracking.17

Perfection is matching the specIn current market conditions, existing and potential usersshould, above all, avoid “over-specifying” when choosing asteel for a given application.Historically, austenitic grade 304 has been the mostwidely developed and readily available stainless steel grade,due to the broad spectrum of applications for which it issuitable. Today’s ferritic stainless steel grades, properlyspecified, can often be substituted for 304, to excellenteffect.Close and realistic examination of the fabricatingand in-service qualities required will often reveal that aneconomically advantageous ferritic grade can perfectlyadequately meet these specifications, for both fabricatorand end-user.Sometimes, a reasonable in-service compromise (e.g.advising end-users to clean their product’s surface regularly)is all that is required to keep a particularly inexpensiveferritic grade immaculately corrosion-free for the life of theproduct.Cladding panels, in coated grade 430, Italy. Kitchen line-up, in grade 430, S. Africa.“Today’s ferritic stainless steelgrades, properly specified, canoften be substituted for 304,to excellent effect.”“A steel whose time has come”Given the quality of today’s ferritic grades, their priceadvantage and the exceptional properties that can be obtainedby using additional alloying elements, the opportunities forferritic stainless steels seem unlimited.This brochure tries to make the qualities of ferriticseasily understandable, describing them in relatively simpleterms. Its aim is to encourage the greater use of stainlesssteels in general by increasing awareness of the merits ofthese lower-cost grades. This is part of a stainless steelindustry initiative to help users specify the correct gradesfor their application.The following pages examine the properties of today’sferritics, the roles of the various alloying elements and themany existing and potential applications of these steels.18

what they’re saying about ferriticsDominique MaretMarketing Director, Faurecia Exhaust Systems, France“As a worldwide automobileequipment supplier, Faurecia’smain use of stainless steels is inexhaust systems. Of the 200,000metric tons or so of stainlesssteel that we use for this purposeannually, some 90 percent isferritic. In fact, we’ve been using ferritics since the mid-1970’s,when we started producing catalytic converters conforming toU.S. emission standards. Ferritics have much lower thermalexpansion characteristics than austenitics, which was acrucial factor in the durability of these catalytic converters.“Ferritics are a success story for us because our deepunderstanding of the specific behaviour of the grades in differentexhaust environments means we can choose the right gradefor the right application. Of course, formability limitations andthe need to avoid intergranular corrosion need to be taken intoaccount in both product design and manufacturing process.We increasingly require continued progress with ferritics inthe areas of high temperature performance above 900°C andcorrosion resistance. We believe that such improvements toferritic grades will bring them closer to the performance ofaustenitics, but still at a lower and more stable cost. That said,we’re already very satisfied with ferritics.”20

Corrosion resistance propertiesStainless steels are “stainless” because their chromium content gives themexceptional resistance to corrosion.All steels are prone to corrosion, to varying degrees. Stainlesssteels, however, are significantly more corrosion resistantthan carbon steels, due to the chromium they contain.Chromium (not nickel, as is sometimes imagined) is the keyingredient in the corrosion resistance of stainless steels.“…ferritics and austenitics canbe seen as two interchangeablestainless steel families.”LOCALISED CORROSION RESISTANCEStainless steel applications are mostly maintenance-freebut, in some cases, light maintenance (removal of deposits,for example) may be necessary, to ensure corrosion-freeservice life.The corrosion resistance of stainless steels is determinedmore by chemical composition than by austenitic or ferriticatomic structure. Indeed, in terms of resistance to corrosion,ferritics and austenitics can be seen as two interchangeablestainless steel families.A comparison of the corrosion–resistance properties ofthe five ferritic “groups” with those of austenitic type 304clearly highlights the key role of chromium and shows thatthe corrosion resistance of nickel-containing (austenitic)grades can be matched by the majority of ferritic families.- corrosion resistance +410L409fERRitic/austEnitic LocaLisEdcoRRosion REsistancE430304441439436316444G1 G2 G3 G4PRE 10 16 17 18 20 24Moisture separator reheater in grade 439, Europe.The above chart shows that only molybdenum-containingferritic grades have better localised (“pitting”) corrosionresistance than 304. However, stabilised ferritic standardgrades, although positioned slightly below 304, still havevery good resistance to pitting corrosion.Radiator grill and trim, in grade 436.Partially 444 building cladding, Brazil.21

Group 1 ferritics are best suited to non-severe conditions,such as inside the home (where the material is either notexposed to water contact or gets regularly wiped dry) oroutdoors in contexts where some superficial corrosion isacceptable. In such contexts, this group of ferritics has alonger life than carbon steel,.The PRE factorThe “PRE” or Pitting Resistance Equivalent number is ameasure of the relative pitting corrosion resistance of astainless steel grade in a chloride-containing environment.The higher a grade’s PRE value, the more corrosion resistantthat grade will be.Group 2 grades are effective in contexts involvingintermittent contact with water, in non-severe conditions.AustENitiC/fERRitiC PRE CoMPARisoNPREN = %Cr = 3,3 x % Mo + 16 x %N35Group 3 grades are suitable for similar contexts to thoseappropriate for Group 2 grades, but are easier to weld.30317lN 446/447SEA wATER 20°CGroup 4 ferritics are more corrosion resistant than type304 and are suitable for a wide variety of uses.252015316304444436430439CoASTAl ENv. 20°CPURE wATERGroup 5 includes, for example, grades with a very highchromium content of around 29% Cr, plus 4% Mo, whichmakes them as corrosion resistant in seawater as titaniummetal.4090AUSTENITICFERRITICThe PRE comparison table shows at a glance that for everyaustenitic grade there is a ferritic grade with comparablecorrosion resistance.In the commonly used shortened form of the PRE formulaPRE=%Cr+3.3%Mo, molybdenum (Mo) is expressed asbeing 3.3 times more effective than chromium againstpitting corrosion. However, chromium is always essentialfor providing the basic corrosion resistance. Molybdenumcannot replace this “base” amount of chromium in stainlesssteels, but can be used to boost corrosion resistance.Nickel content is not considered in the formula, sincein most applications it plays no role in resistance to pittingcorrosion.“Nickel plays no role in resistanceto pitting corrosion.”Storage tank, in grade 444, Brazil.Avoiding corrosionStainless steel’s “passive”layer (see p. 59) needsoxygen to remain intact. Anaccumulation of deposits candeprive the steel of oxygenat critical points, whichcould lead to corrosion.Propagation of corrosionmay lead to eventual ruptureof the part.Barbecue and trolley, in grade 430, Italy.22

Corrosion risk factors• embedded particles• superficial deposits• surface defects• structural discontinuities• salinity (salty areas, seawater, etc.)• increase of temperature• highly acidic conditions (strong acids)• a strongly “reducing” environmentCorrosion-preventing factors• a clean surface• a smooth surface• a pre-passivated surface• ageing of the surface• the washing effect (e.g. rain)• higher chromium content• oxidising conditions (O 2– not too strong)• adding molybdenum23

Corrosion sets in when pH reaches a critically low value(low pH = high acidity). The “pH” level is a unit of measuredescribing the degree of acidity or alkalinity of a solution.This is measured on a scale of 0 to 14.ATMOSPHERIC CORROSIONThis type of corrosion occurs on a steel surface, in the thin,wet film created by a combination of humidity in the air andimpurities. It is often initiated by the presence of chloridesor sulphur compounds – in an industrial environment.Typical conditions could be, for example, chloride depositsin a humid, marine atmosphere.marineAtmospheric corrosion resistAnceRailway station safety barrier, in SUS430J1L, Japan.Choice of gradeFerritic grades can be used in atmospheric environments ofwidely varied corrosive severity. All parameters concerningin-service conditions should be closely considered inselecting the appropriate grade.If slight localised surface rust (pitting corrosion), forexample, is of no importance in a certain application orenvironment, a lower-cost grade might well be the correctmaterial choice.Rules of thumb• In the case of an aggressive environment,select a grade with a higher chromiumand/or molybdenum content.• Avoid rough surface finishes – favour afine-polished surface with a low Ra value.• Optimize design for “washability” (e.g. min.15° slope on upward-facing surfaces).• Avoid “crevice-like” geometries.coastalindustrialrust unacceptable• Keep surface clean, by regular washing,to avoid staining and dust accumulation.cityruralsmall pits acceptableno rustindoor409 410 430 439 304 444 316 447 materialselectionDifferent environments require different ferritic (400-series) or austenitic (300-series)grades, to resist atmospheric corrosion. In industrial, coastal and marine environments,some localised (pitting) corrosion may be acceptable, in certain applications.“Ferritic grades can be usedin atmospheric environmentsof widely varied corrosiveseverity.”Electrification box, in painted grade 410, S. Africa.24

OXIDATION RESISTANCEUnlike the two above types of corrosion, high-temperaturecyclic oxidation is “dry corrosion” occurring at hightemperatures (>500°C) and in oxidizing atmospheres, withor without thermal cycle.When stainless steels are heated, their chromium contentforms a protective chromium oxide surface “scale” thatdelays further oxidation. The scale and the metal substratewill have different thermal expansion behaviour, which canaffect the scale’s stability, especially in service conditionsof frequent thermal cycling. The expansion coefficient ofthe scale is very low and if that of the metal is too high,excessive scale will be generated, which will spall or crackwhen the metal cools and contracts.Thanks to their lower thermal expansion coefficient,ferritic grades are much less prone than austenitic alloysto high-temperature cyclic oxidation scaling. Where thereis no spalling or cracking, there is no new oxidation. Thisis a particular advantage in applications such as heatingsystems, burners or exhaust systems, including manifolds.Broad application possibilitiesThese interesting corrosion-resistance properties are farfrom being ferritic stainless steel’s only attractions. Theyare already enough, however, to win friends for ferritics inthe current climate of high material costs.Close examination of the properties of ferritics tends topay dividends. Some existing austenitic users might find, onexamining their specification, that a ferritic grade is actuallyhighly appropriate for their application.…ferritic grades are much lessprone than austenitic alloysto high-temperature cyclicoxidation scaling.Potential stainless steel users may be surprised by theexceptional qualities of ferritics – and discover that stainlesssteel is a viable option after all!Life Cycle Costing: an invaluable guideThe value of carrying out a Life Cycle Costing study on anypotential application cannot be stressed too highly. Sucha study will often reveal that stainless steel – generallyseen as a costly solution – is actually the lower-cost option,viewed long-term.Stainless steel’s corrosion resistance means longer life,less maintenance, higher resale value, better appearance,etc. It renders painting or galvanizing unnecessary. And asif this were not inducement enough, the lower investmentcost of ferritic grades can be a clinching argument in favourof stainless steel as a material choice.Already widely used and respected, ferritic grades arenonetheless still being “discovered”. The numerous wellprovenexisting applications, however, light the way to manyexciting new possibilities for these fine steels.Burner, in grade 430.Manifold, in grade 441.Gymnasium roof, in grade 445, S. Korea.…the lower investment cost offerritic grades can bethe clinching argument infavour of stainless steel…25

Induction cooking requiresthe magnetic propertiesof ferritic grades.what they’re saying about ferriticsSeung Tae BaekTeam Leader Washing Machine Procurement,LG Electronics, Korea.“We use ferritic stainless steels mostlyin washing-machine drums and havedone so from an early stage in ourdevelopment of automatic washingmachines. In fact, in 2006, we usedsome 15,500 tons of ferritics, against2,500 ton of austenitics, so ferriticsaccounted for 86 percent of our stainlesssteel consumption.“The advantage for us is simply that ferritic grades have verysatisfactory mechanical qualities but are less costly thanaustenitics. Technically, advances in moulding technology andthe development of higher-quality ferritic grades mean wecan use ferritics very successfully these days. Cracking andcreasing in the press remains an occasional source of defectsand we need to improve aspects of the deep drawing process.However, with ferritics we get a result that satisfies everyonein terms of both price and quality.”26

Mechanical and physical propertiesFerritic stainless steel grades are fabrication-friendly and suitable for a verywide range of applications.Ferritics have good mechanical properties, occupying anintermediate position in this respect when compared tothe other stainless steel families. They have higher yieldstrength than austenitics, while their elongation and formingproperties are equivalent to those of carbon steels. Theirphysical properties include two characteristics in whichthey out-perform austenitic grades: thermal expansion andthermal conductivity.Mechanical propertiesGenerally speaking, the mechanical properties of ametallic alloy are those that describe the material’s abilityto compress, stretch, bend, scratch, dent or break. Themost commonly used criteria for evaluating mechanicalcharacteristics are:• Strength: the degree of resistance of a material todeformation. Two critical values are generally considered:• yield strength, or the stress the material can besubjected to before permanent plastic deformationoccurs;• tensile strength, or the stress it can be subjected tobefore rupture/failure.• Hardness: the degree of resistance to indentation by anapplied load.• Toughness: the capacity to absorb deformation energybefore fracture.• Ductility (or plasticity): the ability to deform plasticallywithout fracturing.Some of these properties can be measured by a tensiletest. The resulting stress-strain curves make it possible todetermine yield strength (YS), ultimate tensile strength (UTS)and total elongation at failure (E). These tests result in thedefinition of a stress-strain curve charting the performanceof the metal in response to various loads.STRESS (MPa)UTS600UTS500400YS300YS2001000UTS is measured in MPa (1Mpa = 1N/mm 3 = 145PSI = 0.1kg/mm 3 ) and representsmaximum resistance at failure. YS refers to the beginning of the “plastic” phase, whereelongation no longer disappears when the stress is removed.The stress-strain curves show that while ferritic grade 430has its limits, it clearly performs exceptionally well withinthose limits.MARTENSITICSTAINLESS STEELSHSLA STEELSA36CARBON STEELSFERRITICSSTAINLESS STEELSTYPE 430FERRITIC STAINLESS:EQUIVALENT TOCARBON STEELAUSTENITICSSTAINLESS STEELSTYPE 304/3164 8 12 16 20 24 28 32 36 40 44 48 EISTRAINAUSTENITICS:EASIER TO FORMINTO COMPLEX SHAPES“…ferritics and austenitics canbe seen as two interchangeablestainless steel families.”Bus body frame, in grade 410, S. Africa.STRESS (Ksi)Escalator steps, in grade SUS430, Japan.27

Ferritic stainless steels have stress-strain curves fairlysimilar to those of plain carbon steels. With moderately highyield strength (generally higher than that of austenitics),moderately high ultimate tensile strength and good totalelongation performance, they offer good ductility.Mechanical ProPerties (cold rolled)ASTM A 240 JIS G 4305 EN 10088-2R mminR p02minA 5minR mminR p02minA 5min409 380 170 20 -- -- -- -- X2crti12 1.4512 380-560410s 415 205 22 sUs410430 450 205 22 sUs430440 205 20 X2crni12 1.4003 450-650420 205 22 X6cr17 1.4016 450-600R mR p02minA 80min220 25320 20280 18Boiler inner tube, in grade 444, S. Korea.434 450 240 22 sUs434436 450 240 22 sUs436450 205 22 X6crMo17-1 1.4113 450-630410 245 20 X6crMonb17-1 1.4526 480-560439 415 205 22 -- -- -- -- X2crti17 1.4520 380-530439 415 205 22 -- -- -- -- X2crti17 1.4510 420-600441 415 205 22 -- -- -- -- X2crMonb18 1.4509 430-630s44400(444)415 275 20 sUs444304 205 515 40 sUs304410 245 20 X2crMoti18-2 1.4521 420-640520 205 40 X5crni1-80 1.4301 540-750280 18300 25200 24240 23250 18320 20230 45The above table expresses properties in terms of U.S., Japanese and European standards,comparing ferritic grades with standard austenitic grade 304. Rm = ultimate tensilestrength, Rp02 = yield strength and A5/A80 = elongation to fracture.Physical propertiesThe physical properties of a metallic alloy concern thematerial’s ability to conduct heat, conduct electricity, expandor shrink, etc.Ferritics are magnetic. They also have some otheruseful advantages over austenitic grades. Their thermalconductivity, for instance, is notably high. This means thatthey spread heat comparatively efficiently – which makesthem highly suitable for applications such as electric ironsor heat exchangers (tubes or plates).The thermal expansion coefficient of ferritic stainlesssteels is similar to that of carbon steel and much lowerthan that of austenitic stainless steel. As a result, ferreticsdistort less when heated.PhYSiCal ProPErTiESType ofstainlesssteelDensityElectricresistanceSpecificheatThermalconductivityThermal expansioncoefficientYoung’smodulusx10 3g/cm 3 mm 2 /m 0 ~ 100°CJ/kg • °C100°CW/m • °C0~200°C 0~600°C10 -6 /°CN/mm 2409/41010%-14% Cr43014%-17% Cr7.7 0.58 460 28 11 12 2207.7 0.60 460 26 10.5 11.5 220Soleplate of electric iron, in buffed grade 430.Stabilised430Ti, 439,441Mo > 0,5%434, 436, 444Others17%-30% Cr7.7 0.60 460 26 10.5 11.5 2207.7 0.60 460 26 10.5 11.5 2207.7 0.62 460 25 10.0 11.0 220304 7.9 0.72 500 15 16 18 200Carbon steel 7.7 0.22 460 50 12 14 215The modulus of elasticity of ferritic grades (at 20°C) is superior to that of 304 austenitic.IS units: g/cm 3 = kg/dm 3 – J/kg • °C = J/kg • °K – W/m • C = W/m • K –10-6/°C =10-6/°K – N/mm 3 = MPa.28

As strong as carbon steel,low-chromium ferritic gradesare also corrosion resistant.Ferritic rail ore wagonstherefore have a lowerLife Cycle Cost (LCC).29

Aesthetic and hygienefactors make ferritican ideal materialfor gas hobs.Zhang Sen30what they’re saying about ferriticsDirector of Stainless Steel Purchasing, Qingdao HaierInternational Trading Co. Ltd., People’s Republic of China“As one of the world’s leading white goods home-appliancemanufacturers, the Haier Group usesferritics in a broad range of products,including washing machines, dishwashers, gas cookers, kitchenextractor hoods and microwave ovens.Having started using these gradesbefore the year 2000, we currently usearound 14,500 metric tons of ferriticsa year, representing about 85% of our total stainless steelconsumption. Ferritic grades are less costly than austeniticgrades and are ideally suited to these applications.“Compared with austenitic grade 304, standard ferritics neithermeet the deep-drawing requirements of every part nor showas good corrosion resistance in chloride environments, nordo they have the same welding characteristics. However,they remain excellent materials for home appliances and,in terms of manufacturing, the adapted grades we use havegood punching and drawing properties. So we’re happy withferritics.“With the nickel price going up crazily, our purchasingcosts for stainless steel have increased sharply. Replacingaustenitics with ferritics not only lowers our raw-materialcosts but also saves resources and protects our environment.I would go so far as to say that while austenitics dominatetoday’s stainless steel market, the future of stainless-steelconsumption lies with ferritics.”

Forming ferritic gradesThanks to their good drawing characteristics, ferritic stainless steels can meetthe challenges of complex, three-dimensional designs.Since their use in complex designs does not impair any oftheir remarkable corrosion resistant, heat resistant anddecorative qualities, ferritic grades are often the right choicefor both industrial and consumer products.Stamped top and bottom of boilers, in grade 441, S. Africa.“…some ferritic grades showexcellent drawing performance.”How drawing worksIn the drawing process, shaping of the part is achieved bypressing a flat sheet blank into a die cavity, by means ofa punch. The metal is drawn inwards, slipping betweenthe die and the blankholder to form the walls or “skirt” ofthe part.Deep DrawingCold forming operations change the shape of strip or sheetproducts by subjecting them to plastic strain. The formingoperation involves complex combinations of tensile andcompressive loading, using a combination of stretching anddeep drawing deformations.Although the overall drawing capacity of austeniticgrades is better than that of ferritics, some ferritic grades(notably titanium-stabilised, 17% chromium grades) showexcellent drawing performance.The slipping effect differentiates “drawing” from the “stretch-forming” method, in whichthe blank is constrained by the blankholder.Drawing ferritic gradesDrawing is the process most commonly used for forminghollow objects from a flat sheet or “blank”. The gooddrawing behaviour of ferritic stainless steels, coupled withtheir considerable price advantage, can make ferritics theoptimum choice.Sink, in grade 430, Japan.31

Microwave oven, in grade 430, BA finish, S. Korea.Ferritics have higher LDR values than austenitics, whichmakes them particularly suitable for drawing.LDR gRaDe compaRisonlimited drawing ratio (LDR)2.202.152.102.052.00409 430 439 441 304Successful drawing means• The absence of fracture• Excellent surface aspect• Minimum material consumptionStretch-forming ferritic gradesFerritic grades are inferior to austenitics in pure stretchforming.Stretch forming• High fabrication productivity• Low tool wearThe LDR factorThe Limited Drawing Ratio (LDR) is an important deepdrawabilityparameter.Limited drawing ratio (Ldr)DIn stretch-forming, the drawn area becomes thinner.dLimited Drawing Ratio (LDR) refers to the quotient of themaximum blank diameter (D) that can be deep drawn intoa cylinder in one step and the diameter of that cylinder.LDR = D/d.“Ferritics have higher LDR valuesthan austenitics,which makes them particularlysuitable for drawing.”The table below compares the stretching performanceof various grades “Dome height” refers to the maximumdegree of deformation before “necking” (the phase justbefore failure) of a blank undergoing stretching.dome height (K50) in mm35.030.025.020.015.0Stretch-forming performanceDome height (K50) for different stainless steels409 430 439 441 30432

forming limit curvesIn practice, industrial forming operations involve acombination of both pure drawing and pure stretch-formingdeformation, in a series of “passes”.Forming limit curves are a useful guide to maximumdeformation before failure, in both deep drawing andstretching processes. Established for the principal stainlesssteel grades, they can be used to analyse a formingoperation.major strain 10,70,60,50,40,30,20,10-0,5 -0,4 -0,3 -0,2 -0,1 0 0,1 0,2 0,3 0,4These curves define local deformations during and afterforming in terms of two principal “true strains”: longitudinal(“major strain”) and transverse (“minor strain”). The curvesplot the effects of the various combinations of these twostrains, up to the point of fracture. The higher the positionof its curve the better a grade’s formability.How ferritics behaveGenerally, the work hardening and elongation characteristicsof ferritic stainless steels are comparable to those of highstrengthcarbon steels. They are not the same as those ofaustenitic grades.Design, construction and fabrication parameters andthe material properties of the ferritic grade concerned mustbe considered together, in order to get the best out of thedrawing process.minor strain 2439 460 409436 441 434304Stamped catalytic converterhousing, in grade 441.“Titanium-stabilised grade 430Tiis often chosen to replacean austenitic in applicationsinvolving deep drawing.”“Ridging”After certain forming operations, ferritic grades aresometimes prone to surface phenomena known as “ridging”and “roping”.This defect takes the form of a series of lines or ridges,parallel to the sheet rolling direction. “Ridging” describesthe overall profile of the deformed surface and includesboth the microgeometry modifications and the “roping”undulations caused by the deformation.The addition of a stabilising element, such as titanium, willbring improvement here. Titanium-stabilised grade 430Ti gives remarkableresults in this regardand is thus often chosento replace an austeniticin applications involvingdeep drawing.Stamped manifold, in grade 441. Dryer drum: 409 welded sheet, formed by expansion.Without surface defect.33

LubricationGood lubrication of the blank and the tooling is essential forsuccessful drawing, to avoid altering the surface appearanceand to prevent sticking phenomena detrimental to tool life.If ferritic stainless steels are delivered with a bright,smooth surface, a high-viscosity drawing lubricant maybe used. Lubricants used with stainless steels are specialoils with high pressure resistance and containing little orno chlorine. Uniformly applied on the blank, they are easilyremovable from a stainless steel component after drawing.ToolingUsing the right tooling is vital, since it has a decisive influenceon friction conditions and thus on metal flow during theforming operation. In special cases, tooling (mold and die)can be made of copper, iron or aluminium bronze.The forming propertiesof the main steel groupsThe table below compares theforming properties of ferriticstainless steels (which havea specific metallurgicalstructure and hence specificbehaviour) to those of carbonsteel and austenitic stainlessgrades. It uses standardcriteria applied in definingdeformation characteristics.“Bcc” (body-centred cubic) and “fcc” (face-centred cubic)refer to the particular atomic structure of each type ofsteel.Welded bended tubes of a manifold, in grade 441.Carbon Steel Ferritic SS Austentific SSstructure bcc bcc fccwork hardening low low highspringback low low highdeep drawing excellent good goodstretch forming good good excellentridging no can occur noSurface treatments, such as a TiCN layer, may be applied,to increase the life of the tooling. The blank holder and dietools have to be carefully polished. The punch can remainrough.“Lubricants used with stainlesssteels are easily removable froma component after drawing.”Bending of 430Ti welded tube.1.4003 hydroformed welded tube.Corrugated and finned heat exchangerwelded tubes, in grade 439.Deformation of the weld (1.4003).34

The case for ferriticsWhile the tables and curves show that austenitics aresuperior, overall, in terms of formability, the ferritic costadvantage is such that looking into the use of a ferriticgrade can often pay clear dividends. Favouring the drawingmethod, especially, allows a remarkably wide use of ferriticgrades. Indeed, in certain specific cases – such as deepdrawing or springback effects – ferritics behave better thanaustenitics.Users should thoroughly discuss technical questionsregarding the use of ferritic grades with a reputable materialsupplier. Stainless steel industry expertise is always onhand, to help users find ways to make ferritic grades workand to ensure that the most appropriate grade is chosen forany given application.“…favouring drawing allowsexceptionally wide use offerritic grades.”35

Increasingly stringentanti-pollution regulationsplus technical and economicrequirements make ferriticthe basic material forexhaust systems.what they’re saying about ferriticsBernhard BlaeserDirector, Macadams Baking Systems (PTY) LtdSouth Africa“My company makes baking ovens and provers. With thesubstantial increases in austenitic prices in the recent past,many players in the industry have moved away from or are inthe process of moving away from stainless steel altogether.This is especially so in non-heat applications, like the externalpanels of ovens, and other bakery equipment not directly incontact with food. As ferritic prices have not been as severelyaffected, an alternative is to substitute ferritic. In essencethen, manufacturers should consider substituting austeniticswith ferritics, rather than dropping stainless steel entirely.”36

Joining ferritic gradesFerritic grades are well suited to all the numerous methods of joining stainlesssteels.Adhesive bondingMechanical joining“Ferritic grades have some usefuladvantages over austenitics,when it comes to welding…”Joining methods• Welding: achieving complete joining of two or morematerials through melting and re-solidification of thebase and filler metals.• Soldering: producing joining of materials by heating themto soldering temperature (below the solidus of the basemetal) in the presence of filler metals with a liquidus of< 450°C.Soldering/Brazing• Brazing: the same as soldering but coalescence occurs at> 450°C.• Mechanical joining: includes clinching, seaming, rivetingand mechanical fasteners.Welding• Adhesive bonding: achieved by pressing clean, activatedsurfaces together after applying a bonding agent thatbonds using either oxygen, water or a chemical reaction.WeldingOf the many welding processes developed for carbon steelsthat can be used with stainless steels only a few are reallyappropriate for these materials and have become standard:arc, resistance, electron, laser-beam and friction welding.Welding is the most efficient and least costly way to joinmetals. The process makes possible structures of lighterweight (through the optimal use of materials), joins allcommercial metals and provides design flexibility.The welding characteristics of stainless steels areaffected by chemical composition, metallurgical structureand physical properties. Ferritic grades have some usefuladvantages over austenitics when it comes to welding, sincethey feature lower thermal expansion, lower electricalresistivity and higher thermal conductivity.Stabilised and unstabilised ferritic gradesOn average, ferritic stainless steels tend to be less pronethan austenitics to the intergranular corrosion that canresult from welding.37

This is especially true of “stabilised” ferritic grades, whichcontain strong carbide formers, such as titanium (Ti) andniobium (Nb). These tie up the carbon in the steel, duringthe welding process, preventing it combining with chromiumto form chromium carbide. With consequent chromiumdepletion at grain boundaries prevented, stabilised ferriticgrades are virtually immune to intergranular corrosion.To ensure complete stabilisation, Ti content must be fivetimes greater than carbon content, or Nb plus Ti must bethree times greater than carbon content. Sometimes, theintroduction of nitrogen into this formula can be advisable,to refine the grain in the melted zone.Unstabilised ferritic grades contain no Ti or Nb and cantherefore be susceptible to intergranular corrosion in theheat affected zone, due to chromium carbide formation. Thiseffect is called “sensitisation”. Its extent depends mainly onthe carbon level.The corrosion resistance of sensitised steels can,however, be restored by annealing, at a temperature rangeof 600-800°C.“…stabilised ferritic gradesare virtually immune tointergranular corrosion.”Exhaust system welding, grade 439, S. Korea.Degree of sensitisationTypical typei.e. 430Low (C + N)i.e. 410LGrade weldabilityExtra-low (C + N)+ stabilisationi.e. 430Ti, 409LOvermatching filler metalsTo ensure that a weld will be corrosion resistant, any ferriticfiller metal used should slightly overmatch the compositionof the base metal in terms of Cr, Mo, Ti and/or Nb alloyingelements. This is because heating will tend to cause a lossof chrome in the weld zone. Alternatively, austenitic fillermetal can be used, with an overmatch of Cr and Mo alloyingelements.Protective gasesBeing high in chromium, stainlesssteels are highly oxidizable in themolten state. If they are not protectedfrom air during the welding process,chromium will be lost and oxides will form, resulting inlack of soundness and decreased corrosion resistance inthe weld. Protection of the weld surface and neighbouringarea is usually ensured by the provision of an inert gaseousshield. This shielding gas can either be an inert gas of pureargon (Ar) or helium (He) or a mixture of Ar and He.For the welding of ferritics, these shielding gases shouldbe pure argon or argon-helium mixtures. Argon-hydrogenmixtures, often used for austenitic grades, bring a risk ofhydrogen embrittlement in the weld joint, in the case offerritic grades. Argon is the most commonly employedbacking gas (protecting the rear of the workpiece). Nitrogenmust not be used with ferritic grades.Troubleshooting ferritic welding problemsAs well as the risks referred to above, there can also berisks of embrittlement by “phase formation” and “graincoarsening” at high temperatures. Their solutions are listedin the following “remedies” table.Welded tank, grade 444, Europe.38

WEldinG fERRitiC StEElS: REMEdiESStainless steelgroupSpecial feature Phenomenon Cause How to avoidUnstabilised grades Sensitisation Poor corrosionresistance inwelded zoneCr-carbideprecipitation ingrain boundaryAnnealing intemperature range600-800°CStabilised grades Grain coarsening Poor toughness inwelded zoneHigh Cr-Mo grades 475°CembrittlementHigh Cr-Mo gradesUnstabilised gradesSigma () phaseembrittlementMartensitic phaseembrittlementArc weldingArc welding is the form of welding most commonly employedwith ferritic grades.Gas Tungsten Arc Welding (GTAW or TIG/WIG)In this process (also known as the Tungsten or WolfamInert Gas process), the energy needed to melt the metal issupplied by an electric arc between the tungsten electrodeand the workpiece.Embrittlementoccurs at400~500°CEmbrittlementoccurs at550~800°CEmbrittlementoccurs in lower Crand higher-C typesExcessive graingrowth due to hightemperatureSigma () phaseformationdue to decompositionof phaseSigma () phaseformationMartensitic phaseformation due tofaster coolingMinimising the heatinput of weldingReheating at 600°Cand cooling rapidlyReheating above800°C and coolingrapidlyRemoving themartensitic phaseby long annealingin the 600-700°CrangeGas Metal Arc Welding (GMAW or MIG)Unlike the GTAW process, in GMAW (also known as the MetalInert Gas process), the electrode is consumable. The arc isstruck between the molten filler wire and the workpiece.The shielding gas, injected through the torch, around thewire, is usually argon with an addition of 2% to 3% oxygen,though more complex mixtures may be used for certainwelding modes.Since the weld is essentially composed of filler metal, itis vital that the filler metal’s composition should promotepenetration and perfect wetting of the base metal.This high-productivity process is more difficult to performthan GTAW welding but results can be excellent when theprocess is well controlled.Ferritic tube mill, Brazil.Resistance weldingIn resistance welding, an electric current is passed throughthe parts to be joined and welding is caused by resistanceheating.Stainless steels are always welded in the straight-polarityDC mode (the electrode being the negative pole), under aninert atmosphere. If a filler metal is used, this will be inthe form of uncoated rods (manual welding) or coiled wire(automatic welding).Welded tank, grade 441, S. Africa.Welded structural frame in grade 1.4003.39

Several resistance welding techniques exist, the mostcommon being spot welding and seam welding. In bothcases, the major advantages of resistance welding are:• the limited modification of the microstructure in the heataffected zones (HAZ);• the virtual absence of surface oxidation, if the sheets arecorrectly cooled;• the very low level of distortion of the sheets afterwelding;• “forging” deformation during welding, which is particularlyuseful for the joining of ferritic steels.Compared to the requirements of mild steel, the maindifferences in process parameters for stainless steel arethe lower and more precisely adjusted welding powers (dueto low electrical and thermal conductivities) and higherelectrode forces.Other processesOther welding processes applicable to ferritic stainlesssteels include electron and laser beam welding and frictionwelding.Soldering and brazingSoldering and brazing are processes for joining metalliccomponents in the solid state by means of a fusible fillermetal that has a melting point well below those of the basemetals. Soldering employs soft filler alloys with meltingpoints below 450°C, whereas brazing alloys are harder andmelt at higher temperatures.The advantages of these joining techniques include thefollowing convenient features:• They require only a low-temperature heat source.• Joints can be permanent or temporary.• Dissimilar materials can be joined.• The rate of heating and cooling is slow.• Parts of varying thicknesses can be joined.• Realignment is easy.• They require less heat than welding.In deciding on the suitability of soldering or brazing for aspecific structural joint, care should be taken to evaluatecarefully the strength or performance required of the joint.In all cases, while carrying out the joining, it is essentialto ensure perfect wetting of the two solid parts by the moltenfiller material.Sensitisation will occur more readily in the case ofunstabilised grades.Pickling, passivationand decontaminationBrazing welded tubes, grade 441.Soldering a gutter, tin-coated grade 430Ti.The slight discoloration resulting from welding shouldbe eliminated by either mechanical descaling or achemical treatment called pickling.Pickling is carried out in a fluonitric solution(10%HNO3 + 2%HF) or using pickling pastes designedspecially for welds.It can be followed by a passivation and decontaminationtreatment – to help the passive layer (see p. 59) reformquickly and remove organic metallic residues (iron-richparticles). The process involves immersion in a cold20%-25% nitric acid bath.Local passivation of weld zones can also be carriedout by means of special passivating pastes.40

Mechanical joiningMechanical joining techniques used for carbon steels can beequally successfully used with stainless steels.Mechanical fastenersScrewsSelf-piercing andthread-forming screwsMechanical joining has certain advantages:• Dissimilar materials can easily be joined.• There is no heat affected zone (HAZ).• Parts of varying thicknesses can be joined.• There is no thermal expansion.Consideration should, however, be given to the fact thatthe mechanical properties of mechanical joints may havecertain weaknesses, since there is no complete coalescenceof the joining partners. The joining operation method mayalso require two-side access.It is vital to ensure that none of the surfaces in contactare liable to induce corrosion due to galvanic coupling.To avoid this risk, parts to be joined should preferably bemade from the same stainless steel or an equivalent grade.Certainly any screws, bolts, fasteners or rivets should be ofstainless steel.Screwing and boltingMechanical joining of stainless steelsWithout anyadditional partClinchingSeamingRivetingSelf-piercing rivetsStainless steel screws and bolts are available in all theprincipal grades. While 17% Cr ferritic grades are bestsuited to use in only mildly aggressive environments,their corrosion resistance in chloride-containing media isenhanced by the addition of 1% to 1.5% molybdenum.RivetingThis technique is always carried out at ambient temperature,using rivets of a maximum diameter of about 5 mm. It isstrongly recommended that joints be designed in such a waythat the rivets are loaded in shear rather than in tension.ClinchingThis relatively recent joining technique can be readily appliedto stainless steels, thanks to their high ductility. Being acold forming process, it causes no structural modificationor surface oxidation.Since the sheets to be joined must overlap, clinching isusually combined with an adhesive bonding, producing ahermetically sealed joint, to avoid risk of crevice corrosion.This can also damp vibrations.SeamingIn this mechanical sheet-joining technique, the edges of oneor both of the sheets concerned are bent through an angleof 180°, to produce a tight seam. As with clinching, differentmaterials can be joined – for example, an austenitic and aferritic grade.Perfectly leak-proof joints can be achieved with thistechnique, which is widely used in the manufacture ofdomestic appliances.Exploded display of washing-machine interior. Auto-riveting on 430, 1.5 mm.41

Adhesive bondingAdhesive bonding can be employed to reinforce mechanicaljoints, and in its own right for joining thin stainless steelsheets.Bonding of guttering, tin-coated 430Ti.It is also possible that a smooth-surfaced stainless steel(especially bright annealed) will not have good adhesiveproperties.After roughening, surfaces should be very clean, dry andwell prepared. The essential condition for good bonding issatisfactory wetting of the substrate by the adhesive.As an example of adhesive bonding, bus and coachmanufacturers now often construct a body frame of stainlesssteel shaped sections, often in ferritic grade 1.4003/410.The skin (sheet and/or glass) is adhesively bonded to thisbody frame. This approach increases the vehicle’s life andreduces its weight.The advantages of adhesive bonding are:• There is no modification of the surface appearance,geometry or microstructure of the assembled areas.• Dissimilar materials can be joined easily andaesthetically.• Correctly designed, joints can have excellent fatiguestrength.• The method can provide thermal, electrical or acousticinsulation.• Parts of varying thickness can be joined.Points to take into consideration, however, include thefact that such joints will tend to have a temperature limitof 200°C and will have a certain sensitivity to moisture.Adhesive joints will not be as strong as joints produced bywelding or brazing. For this reason they are mostly usedto produce lap joints, with the load spread over a sufficientarea to limit local stresses.Windows bonded to a 1.4003 tubular frame.42

what they’re saying about ferriticsNick McDonaldMarketing Manager, Lincat Limited,Lincoln, UK“Established in 1971, Lincathas been a front runner in themanufacture of professionalkitchen equipment for 36 years.Grade 430 ferritic stainless steel,which we’ve used from the start,is the absolute bedrock of ourproduct range.“This grade ideally matches the spec of these applicationsand is an economical way of enjoying the advantagesof stainless steel, which are so important when dealingwith food preparation and presentation. In addition,430’s relatively low thermal expansion characteristic isa big technical plus in high-temperature applications.We make virtually everything in 430 ferritic, except somecomponents, such as the inner tanks of wet-well bains-marie,where we are still using 304. On the fabrication side, ourproducts are designed to be very easy to keep clean and 430 isan easy material to work with in this respect.“Staying closely in touch with our customers’ needs, we’vebuilt a reputation for outstanding product reliability and sturdy,durable construction. Grade 430 ferritic is an essential part ofthe equation. We and our customers are very satisfied with it.”44

Products and applicationsFerritics are often associated with decorative trim, sinks and car exhausts. Theiractual and potential usefulness extends far beyond these narrow confines…Ferritic stainless steels are straight chromium steels,containing no nickel. They resist corrosion and oxidation, arehighly resistant to stress corrosion cracking, are usefullymagnetic and offer a host of other technical, aesthetic andpractical advantages. They often prove better value in thelong run than carbon steel and are significantly less costlythan their nickel-containing, austenitic cousins.AUTOMOTIVETheir range of uses is currently under-explored and thepages that follow show something of the range of possibleuses of these materials. The chapter covers applicationsfrom many sectors of the market and many parts of theworld.This publication aims to inspire actual and potential usersof ferritic stainless steels by illustrating existing, successfulapplications. It further aims to encourage responsible andinformed material selection – optimal matching of materialand application has never been more important.EXHAUST SYSTEMCOMPONENTSEXHAUST SYSTEMCOMPONENTSEXHAUST SYSTEMCOMPONENTSEXHAUST SYSTEMCOMPONENTSGrade 1.4509/441, dieselparticle filter, Peugeot 607,FaureciaGrade 1.4509/441,manifold, FaureciaGrade 1.4512/409, silencer,Faurecia, S. KoreaGrade 304 & 441, dieselparticle filter, E ClassMercedes, FaureciaEXHAUST SYSTEMCOMPONENTSEXHAUST SYSTEMCOMPONENTSDecorative trimDecorative trimGrade SUS430J1L catalyticconverter shell, honeycombin 20%Cr-5%AlGrade 1.4509/441, catalyticconverter, FaureciaGrade SUS430, S. KoreaGrade SUS430J1L, Japan45

AUTOMOTIVEDecorative trimDECORATIVE TRIMDECORATIVE TRIMS.U.V. FRONT ELEMENTGrade SUS430, S. KoreaGrade 1.4016/430, blackcoatedtrim, USAGrade 1.4113/434, USAGrade 1. 4513, PlasticOmnium, FranceCAR BOOT SILLHeadlightTruckCLAMPSGrade 1.4510/430Ti,Peugeot 307, FranceGrade 1.4513, headlighttrim, ItalyGrade 1.4113, truckdecorative trim, USAGrades 1.4509/441and 1.4016/430FILTERSBRAKE DISCSTHERMOSTATPADDLE WHEELGrade 1.4512/409L, TaiwanGrade 1.4028/420Grade 1.4512/409, FranceGrade 1.4512/409,1.5 mm thick, France46

BUILDING & CONSTRUCTIONAccessoriesIRONMONGERY – WINDOWHINGES & FASTENERSGutteringGutteringCHIMNEY DUCTGrade 1.4016/430, EuropeGrade 1.4510/430Ti,tin-coated, EuropeGrade 1.4521/444, EuropeGrade 1.4521/444, EuropeConstructionSQUARE-TUBE EXTERIORINSULATING MEMBERSEMERGENCY HOUSINGCOMMUNICATION-SYSTEMSHELTERFactory buildingGrade SUH 409L (1.4512/409),JSSA, JapanGrade 1.4016/430,painted, VERNEST ® andCentro Inox, ItalyGrade SUS 436L (1.4526/436),JSSA, JapanGrade 1.4003, Columbus newfinishing mill, S.AfricaRoof StructureBuildingBuildingBuildingRoof-support: a potentialapplication for ferritics.Grade 445J1L &445J2, Nakano SakaueBldg., 1996, JapanResin coated SUS445J2,Phoenix Resort, 1994, JapanOuter parts SUS445J1,inner SUS304, NihonbashiMitsui Bldg., 2005, Japan47

Civil constructionBUILDING & CONSTRUCTIONNOISE-ABSORBING PLATEFOR OVERPASSGrade SUS 436 (1.4526/436),JSSA, JapanWINDBREAKER FENCESTRUCTURAL STEELWORKOF BRIDGEGrade 1.4003/410 painted,SASSDA, South Africa (bridgein service for over 8 years).PLATFORM SCREEN DOORINNER WALL OF TUNNELGrade SUS 430J1l (1.4016/430),JSSA, JapanElectrification MastsINNER WALL OF TUNNELGrade 1.4016/430, painted,Monte Mario Tunnel,Centro Inox, Italypower generationGrade SUS 445J2, JSSA, JapanGrade 1.4510/439, hair-linefinish, KOSA, S. KoreaGrade 1.4003 (first majorapplication in 1982, alongseashore – 10m from surf,no corrosion), S. AfricaGrade 1.4003/ 410, X-gridcooling tower packing, S.AfricaCladdingBUILDING FAÇADE CLADDINGBUILDING FAÇADE CLADDINGBUILDING FAÇADE CLADDINGBUILDING FAÇADE CLADDINGGrade SUS 445M2,low-reflectivity matt finish,ASSDA, AustraliaGrade 1.4521/444 brushedno. 4 (horizontal panels),Vivo Building, Rio deJaneiro, Nucleo Inox, Brazil(coastal environment)Grade SUS 445J2,Future Science Museum,JSSA, JapanGrade 1.4526/436, Ugine& Alz Steel Service Centre,Arcelor Mittal Stainless,Katowice, Poland48

LiftsRoofingESCALATOR STEPSGrade SUS 430LX(1.4016/430), JapanGYMNASIUM ROOFLIFT PANELSGrade 1.4510/439CANOPYMediadome RoofGrade SUS445J2, KitakyushuMediadome (FukuokaPref.)1998, JapanCHALET ROOFSchool ROOFGrade 430Ti (standingseam technique), Ugine& Alz, AustriaAIRPORT ROOFBUILDING & CONSTRUCTIONGrade 445, KOSA, S. KoreaGrade 446, KOSA,Seoul, S. Korea.Grade 1.4510/430Ti (standingseamtechnique), Ugine & Alz,Germany.Grade SUS 447J1, KansaiAirport terminal building(architect Renzo Piano),JSSA, Osaka, JapanUrban furnitureLAMP POSTPOST BOXESTICKET MACHINE ONRAILWAY PLATFORMELECTRIFICATION BOXESGrade 1.4510/439, electropolishedwelded pipe,KOSA, Seoul, S. KoreaGrade 1.4003/410, painted,SASSDA, South Africa.“Utility” ferritics are oftenpainted, when aestheticconsiderations are important.Grade 1.4003/410, painted (15years in service), SASSDA, UKGrade 1.4003/410, painted(15 years in service), SASSDA,South Africa49

FOOD COMMERCIAL EQUIPMENTBAKERy OVENGAS COOKING EQUIPMENTCOFFEE SERVERHEATED MERCHANDISERGrade 430, Macadams BakingSystems (PTY) Ltd, S. AfricaGrade 430, Lincat, UKGrade SUS430J1, JSSA, JapanGrade 430, Lincat, UKCONVEYOR TOASTERMICROWAVE OVENBURNER RANGEREFRIGERATORGrade 430, Lincat, UKGrade 430 (interior andexterior), JSSA, JapanGrade 430 (gas hob),POSCO, S. KoreaResin-coated SUS 430J1L panel, JSSA, JapanCOFFEE MACHINERESTAURANT TROLLEYDISPLAY MERCHANDISERWALL CUPBOARDGrade 430, Lincat, UKGrade 430Grade 430, Lincat, UKGrade 430, Lincat, UK50

HOME & OFFICEIn the following applications, ferritic (400-series) grades are now established as ideal, on grounds of their aesthetic quality,their resistance to cleaning and disinfection agents, their low thermal expansion coefficient and their magnetism (forinduction cooking). They also offer considerable economic advantages over other materials.Domestic cookingequipmentGAS COOKERVARIOUSMICROWAVE OVENGAS COOKING TOPKOSA, S. KoreaTKN, GermanyGrade SUS430J1, JSSA, JapanTSSDA, ThailandCookware and potsBARBECUEBARBECUEWOKINDUCTION COOKWAREGrade 1.4016/430, windscreenand brazier, Compagriland Centro Inox, ItalyGrade 1.4016/430barbecue, USAGroupe SEB (Tefal)DishwashersPRESSURE COOKERPansDISHWASHERDISHWASHERGrade 430, Groupe SEBGrade 430, POSCO, S. KoreaGrade 430 interior panelResin coated SUS430J1Louter panel, JSSA, Japan51

Electrical appliancesHOME & OFFICEDISHWASHERGrade 430 (exterior andinterior panel), Haier, PRCMixerGrade 1.4513, TKN, ItalyMIXERGrade 430ELECTRIC RICE COOKERResin coated SUS430,JSSA, JapanEquipmentELECTRIC KETTLESHELVESRUBBISH CONTAINERPARTITIONResin coated SUS430,JSSA, JapanGrade 1.4016/430, horizontalshelves, Graepel andCentro Inox, ItalyGrade 1.4016/430, Graepel andCentro Inox, ItalyGrade 430, POSCO, S. KoreaHoodsHANDRAILLCD FRAMEKITCHEN HOODKITCHEN HOODGrade 430 welded tubeGrade 410, POSCO, S. KoreaGrade 430, Blanco,TKN, GermanyGrade 430, Falmec,Nucleo Inox, Brazil52

KitchenwareRefrigeratorsLIQUID DISPENSERGrade 430ELECTRIC KETTLEGrade 430, Groupe SEBPasta cooking potSingle layer SUS430J1L(induction heating),JSSA, JapanFRIDGE & FREEZERGrade 430 panelHOME & OFFICESinksWashing machinesFRIDGE & FREEZERDOMESTIC KITCHEN SINKDRUMDRUMGrade 430 door panel,TKN, GermanyGrade 430, Tramontina, BrazilGrade 430 (drum and exteriorpanel), TKN, GermanyGrade 430 drum, LGElectronics, S. KoreaDryersTablewareDRUMDRUMASIAN SPOONCUTLERYGrade SUS430, JSSA, JapanGrade 409, Whirlpool, EuropeGrade 430400-series grades, IKEA53

INDUSTRYFerritic is extensively used where the maintenance of carbon steel is a virtual impossibility.DAM OUTLET PIPESFLOOD CONTROL GATESTANKsFRACTIONATING COLUMNPainted grade 1.4003/410,Columbus, S. AfricaPainted grade 1.4003/410,Columbus, S. AfricaGrade SUS430J1L, colouredresincoated (outerjacket), JSSA, JapanGrade 410S, EuropeBurnersBoilersCONVEYOR BELTBURNERSBURNERBOILER INNER TUBEGrade 410S, EuropeGrade 1.4509/441 (highoxidation resistance)Grade SUS430, boiler gasburner, JSSA, Japan.Grade 1.4521/444,KOSA, S. Korea“HYDROBOIL” INSTANTBOILING WATER HEATERBoilerHOT WATER TANKHOT WATER TANKGrade 1.4521/444,ZIP Industries andASSDA, AustraliaGrade 444, EuropeGrade 1.4521/444, EuropeGrade SUS444, JSSA, Japan54

Food processingWALLS & CEILINGSHeat exchangersMOISTURE SEPARATORREHEATER WELDED TUBESSubstitution from cupro-nickel (due to erosion by vapour and migration of copper), carbonsteel (erosion problems) and 304 (higher thermal expansion than the carbon steel frame).FEEDWATER HEATERWELDED TUBESCONDENSER WELDED TUBESIndustryGrade 445M2, Melbourne,AustraliaGrade 1.4510/439,VALTIMET, EuropeGrade 1.4510/439,VALTIMET, EuropeGrade 1.4510/439,VALTIMET, EuropeSolar water heatersSugar industrySOLAR WATER HEATERSOLAR WATER HEATERSOLAR WATER HEATERCONVEYOR SYSTEMGrade SUS444, SuncueCompany Ltd. andYUSCO, TaiwanGrade 1.4509/441, Sun Tankand SASSDA, S. AfricaGrade 444 solar panel,SASSDA, S. AfricaGrade 1.4003/410, Columbus,S. Africa. Here, ferritic haslasted over 18 years.SLATE CARRIERSCALDING JUICEHEATER COVERHEAT EXHANGER TUBESCRYSTALISER & DIFFUSERGrade 1.4003/410, Columbus,S. Africa. This machine hasbeen in service 22 years.Grade 1.4003/410, Columbus,S. Africa. Carbon steel (top)compared to ferritic (bottom)after 6 years in service.Grade 1.4521/444, Nucleo Inox,BrazilGrade 1.4003/410, Columbus,S. Africa55

TanksIndustryWATER TANKS & PIPESWATER TANKWATER TANKWATER TANKGrade 444, Brazil.Grade 444, KOSA, S. KoreaPartially in grade SUS 444,finish no. 4, JSSA, JapanPartially in grade SUS 444,finish no. 4, JSSA, JapanMOTORCYCLEFERMENTATION ANDSTORAGE TANKFERMENTATION ANDSTORAGE TANKMOTORCYCLE EXHAUSTMOTORCYCLE EXHAUSTGrade 444, Nucleo Inox,Brazil. Sander Inox hassuccessfully produced suchtanks for 7 years.Grade 444, Nucleo Inox, BrazilGrade 1.4512/409L,YUSCO, TaiwanGrade 1.4509/441, Centro Inox,Italy. The new Vespa ET2is equipped with a ferriticcatalytic silencer.MOTORCYCLE EXHAUSTMOTORCYCLE EXHAUSTDISC BRAKE ROTORVARIOUSGrade 409LGrade 409L, Acesita, BrazilGrade SUS410SM1,JSSA, JapanGrade 420 brake dics, 1.4113decorative trim, Italy56

TRANSPORTATIONBUS & COACH BODY FRAMEBUS & COACH BODY FRAMEBUS BODY FRAMECONTAINERGrade 1.4003/410, Columbus,S. Africa.Grade 1.4003/410 (lower partpainted), Columbus, S. Africa.Grade 1.4003 weldedtubes and panel, SolarisBus & Coach Co. PolandGrade 1.4003/410 (frame andpanels), POSCO, S. KoreaCONTAINERCOAL WAGONCOAL WAGONCOAL WAGONSGrade 1.4003/410, painted(frame and door panels)Grade 1.4003/410 (panels),Columbus, S. Africa. Inservice for over 20 years.Grade 1.4003/410 (panels),Columbus, S. Africa. Inservice for over 15 years.Grade 1.4003 (interior ofprevious), SASSDA, S. AfricaCoal WagonCOAL WAGONCOAL WAGONTramwayGrade 1.4003/410,painted, EuropeGrade 409/410, painted,TISCO, PRCGrade 1.4003,SASSDA, S. AfricaGrade 1.4003/410 (body frameand painted panels), Europe57

AppendicesThe chemical compositionTypes 409, 410, 420of ferritic stainless Cr steelscontent: 10%-14%sTANdArd ferrITIC grAdes91% of total volume in 2006Group 1 Group 2 Group 310%-14% 14%-18%Type 430Cr content: 14%-18%14%-18%stabilised30% 48% 13%Types 430Ti, 439, 441, etc.Cr content: 14%-18%.Include stabilising elementssuch as Ti, Nb, etc.Ferritic stainless steels have properties similar to those of mild steel but showmuch better corrosion resistance. Their development began over a century ago.Early ferriticsStainless steel was “discovered” around 1900–1915. Aswith many discoveries, it was actually the result of theaccumulated efforts of several scientists. Research waspublished in England, France and Germany on alloys withcompositions that would be known today as the 410, 420,430, 442, 446 and 440C grades.Stainless steels must have a very low level of carbon.For many years it was difficult to obtain such a low carbonlevel, which explains the late arrival of good ferritic grades(in the 1980s).The grades and their chemistriesChromium (Cr) is by far the most important alloying elementin the production of stainless steel. It forms the “passive”surface film that makes stainless steel corrosion resistantand increases scaling resistance, wear resistance andtensile strength.speCIAl ferrITIC grAdes9% of volume in 2006A minimum of 10.5% chromium content (by weight) isGroup 4 Group 5required for the protective, self-repairing surface layer ofchromium oxide to form reliably. The higher the chromiumAdded Mocontent, the stronger the passive layer.Types 434, 436, 444, etc.Mo content above 0.5%If the stainless steel surface is machined or accidentallydamaged, the passive layer instantaneously re-forms, in thepresence of air or water.Chemical composition andinternational standardsThe following tables show the chemical analysis of the fivegroups of ferritic stainless steels.Others7% 2%Cr content: 18%-30%or not belongingto the other groupsThe passivation processThe 5 grOups Of ferrITIC grAdesGroup 1 Group 2 Group 3 Group 4 Group 510%-14% 14%-18%14%-18%stabilisedAdded MoOthersTypes 409,410, 420Cr content:10%-14%Type 430Cr content:14%-18%Types 430Ti,439, 441, etc.Cr content:14%-18%.Includestabilisingelements suchas Ti, Nb, etc.Types 434, 436,444, etc.Mo contentabove 0.5%Cr content of18%-30% ornot belongingto the othergroups59

Standards: - ASTM A 280 - 06C, Nov. 2006- EN 10088-2, Sept. 2005- JIS G 4305, 1991Group 1AISI, ASTMChemical component (Maximum weight %)Standard Ref.C Si Mn P S Cr Mo Ti Nb Cu Al N Ni403(M) 0.15 0.5 1.0 0.04 0.03 11.5-13.0 JIS SUS4030.12-0.17 1.0 1.0 0.04 0.015 12.0-14.0 EN 1.4024405 0.08 1.0 1.0 0.04 0.03 11.5-14.5 0.1-0.3 0.6 UNS S405000.08 1.0 1.0 0.04 0.015 12.0-14.0 EN 1.40000.08 1.0 1.0 0.04 0.015 12.0-14.0 0.1-0.3 EN 1.40020.08 1.0 1.0 0.04 0.03 11.5-14.5 0.1-0.3 JIS SUS405409L 0.03 1.0 1.0 0.04 0.02 10.5-11.7 6x(C+N)-0.5 0.17 0.03 0.5 UNS S409100.03 1.0 1.0 0.04 0.02 10.5-11.7 8x(C+N)-0.5 0.1 0.03 0.5 UNS S409200.03 1.0 1.0 0.04 0.02 10.5-11.7 [0.08+8x(C+N)]-0.75 0.03 0.5 UNS S409300.03 1.0 1.0 0.04 0.02 10.5-11.7 0.05-0.2 0.18-0.4 0.03 0.5 UNS S409450.03 1.0 1.0 0.04 0.02 10.5-11.7 6x(C+N)-0.75 0.03 0.5-1.0 UNS S409750.03 1.0 1.5 0.04 0.015 10.5-12.5 0.03 0.3-1.0 UNS S409770.03 1.0 1.0 0.04 0.015 10.5-12.5 6x(C+N)-0.65 0.5 EN 1.45120.08 0.7 1.5 0.04 0.015 10.5-12.5 0.05-0.35 0.5-1.5 EN 1.45160.03 1.0 1.0 0.04 0.03 10.5-11.75 6xC-0.75 0.6 JIS SUH409L10%-14%Cr410(M) 0.08-0.15 1.0 1.0 0.04 0.03 11.5-13.5 0.75 UNS S410000.08-0.15 1.0 1.5 0.04 0.015 11.5-13.5 0.75 EN 1.40060.15 1.0 1.0 0.04 0.03 11.5-13.5 JIS SUS410410L 0.03 1.0 1.5 0.04 0.03 10.5-12.5 0.03 1.5 UNS S410030.03 1.0 1.0 0.04 0.03 12.0-13.0 9(C+N)-0.6 0.03 0.5 UNS S410450.04 1.0 1.0 0.045 0.03 10.5-12.5 0.1 0.6-1.10 UNS S410500.03 1.0 1.0 0.04 0.03 11.0-13.5 JIS SUS410L0.03 1.0 1.5 0.04 0.015 10.5-12.5 0.3-1.0 EN 1.4003410S(M) 0.08 1.0 1.0 0.04 0.03 11.5-13.5 0.6 UNS S410080.08 1.0 1.0 0.04 0.03 11.5-13.5 0.6 JIS SUS410S420J1(M) 0.16-0.25 1.0 1.0 0.04 0.03 12.0-14.0 JIS SUS420J10.16-0.25 1.0 1.5 0.04 0.015 12.0-14.0 EN 1.4021420J2(M) 0.26-0.40 1.0 1.0 0.04 0.03 12.0-14.0 JIS SUS420J20.26-0.35 1.0 1.5 0.04 0.015 12.0-14.0 EN 1.40280.36-0.42 1.0 1.0 0.04 0.015 12.5-14.5 EN 1.40310.43-0.50 1.0 1.0 0.04 0.015 12.5-14.5 EN 1.4034Group 2AISI, ASTMChemical component (Maximum weight %)Standard Ref.C Si Mn P S Cr Mo Ti Nb Cu Al N Ni420 0.08 1.0 1.0 0.045 0.03 13.5-15.5 0.2-1.2 0.3-0.5 1.0-2.5 UNS S420350.08 1.0 1.0 0.04 0.015 13.5-15.5 0.2-1.2 0.3-0.5 1.0-2.5 EN 1.4589429 0.12 1.0 1.0 0.04 0.03 14.0-16.0 UNS S429000.12 1.0 1.0 0.04 0.03 14.0-16.0 JIS SUS42914%-18%Cr429J1(M) 0.25-0.4.0 1.0 1.0 0.04 0.03 15.0-17.0 JIS SUS429J1430 0.12 1.0 1.0 0.04 0.03 16.0-18.0 0.75 UNS S430000.08 1.0 1.0 0.04 0.015 16.0-18.0 EN 1.40160.12 0.75 1.0 0.04 0.03 16.0-18.0 JIS SUS4301.4017 0.08 1.0 1.0 0.04 0.015 16.0-18.0 1.2-1.6 EN 1.4017440(M) 0.6-0.75 1.0 1.0 0.04 0.03 16.0-18.0 JIS SUS440A60

Group 3Chemical component (Maximum weight %)AISI, ASTMStandard Ref.C Si Mn P S Cr Mo Ti Nb Cu Al N Ni430J1L 0.025 1.0 1.0 0.04 0.03 16.0-20.0 8x(C+N)-0.8 0.3-0.8 0.025 JIS SUS430J1L430LX 0.03 0.75 1.0 0.04 0.03 16.0-19.0 0.1-1.0 0.6 JIS SUS430LX439 0.03 1.0 1.0 0.04 0.03 17.0-19.0 [0.2+4x(C+N)]-1.10 0.15 0.03 0.5 UNS S430350,05 1.0 1.0 0.04 0.015 16.0-18.0 [0.15+4x(C+N)]-0.8 EN 1.451014%-18%Crstabilised0.03 1.0 1.0 0.04 0.03 17.0-19.0 [0.2+4x(C+N)]-0.75 0.15 0.03 0.5 UNS S439320.03 1.0 1.0 0.04 0.015 17.5-18.5 0.1-0.6 [0.3+(3xC)] UNS S439400.03 1.0 1.0 0.04 0.015 16.0-17.5 0.35-0.55 EN 1.45900.025 0.5 0.5 0.04 0.015 16.0-18.0 0.3-0.6 EN 1.45200.02 1.0 1.0 0.04 0.015 13.0-15.0 0.2-0.6 EN 1.4595430Ti 0.05 1.0 1.0 0.4 0.015 16.0-18.0 0.6 EN 1.4511441 0.03 1.0 1.0 0.04 0.03 17.5-18.5 0.1-0.6 9xC+0.3-1 1.0 UNS S441000.03 1.0 1.0 0.04 0.015 17.5-18.5 0.1-0.6 3xC+0.3-1 EN 1.4509Group 4Chemical component (Maximum weight %)AISI, ASTMStandard Ref.C Si Mn P S Cr Mo Ti Nb Cu Al N Ni Other415 0.05 0.6 0.5-1.0 0.03 0.03 11.5-14.0 0.5-1.0 3.5-5.5 UNS S41500434 0.12 1.0 1.0 0.04 0.03 16.0-18.0 0.75-1.25 UNS S434000.08 0.75 0.8 0.04 0.015 16.0-18.0 0.9-1.4 EN 1.41130.08 1.0 1.0 0.04 0.015 16.0-18.0 0.8-1.4 [7x(C+N)+0.1]-1.0 0.04 EN 1.45260.12 1.0 1.0 0.04 0.03 16.0-18.0 0.75-1.25 JIS SUS 434436 0.12 1.0 1.0 0.04 0.03 16.0-18.0 0.75-1.25 8x(C+N)-0.8 0.025 UNS S436000.025 1.0 1.0 0.04 0.015 16.0-18.0 0.9-1.4 0.3-0.6 EN 1.45130.025 1.0 1.0 0.04 0.03 16.0-19.0 0.75-1.25 8x(C+N)-0.8 0.025 JIS SUS 436L1.4419(M) 0.36-0.42 1.0 1.0 0.04 0.015 13.0-14.5 0.6-1.0 EN 1.4419Added Mo1.4110(M) 0.48-0.60 1.0 1.0 0.04 0.015 13.0-15.0 0.5-0.8 V≤0.15 EN 1.41101.4116(M) 0.45-0.55 1.0 1.0 0.04 0.015 14.0-15.0 0.5-0.8 0.1≤V≤0.2 EN 1.41161.4122(M) 0.33-0.45 1.0 1.5 0.04 0.015 15.5-17.5 0.8-1.3 ≤1.0 EN 1.41221.4313(M) ≤0.05 0.7 1.5 0.04 0.015 12.0-14.0 0.3-0.7 ≥0.02 3.5-4.5 EN 1.43131.4418(M) ≤0.06 0.7 1.5 0.04 0.015 15.0-17.0 0.8-1.5 ≥0.02 4.0-6.0 EN 1.4418436J1L 0.025 1.0 1.0 0.04 0.03 17.0-20.0 0.4-0.8 8x(C+N)-0.8 0.025 JIS SUS 436J1L444 0.025 1.0 0.7-1.5 0.04 0.03 17.5-19.5 1.75-2.5 0.2+4(C+N)-0.8 1.0 UNS S444000.025 1.0 1.0 0.04 0.015 17.0-20.0 1.8-2.5 4x(C+N)+0.15-0.8 0.03 EN 1.45210.025 1.0 1.0 0.04 0.03 17.0-20.0 1.75-2.5 8x(C+N)-0.8 0.025 JIS SUS 444Group 5Chemical component (Maximum weight %)AISI, ASTMStandard Ref.C Si Mn P S Cr Mo Ti Nb Cu Al N Ni445 0.02 1.0 1.0 0.04 0.012 19.0-21.0 10X(C+N)-0.8 0.3-0.6 0.03 0.6 UNS S44500445J1 0.025 1.0 1.0 0.04 0.03 21.0-24.0 0.7-1.5 0.025 JIS SUS445J1445J2 0.025 1.0 1.0 0.04 0.03 21.0-24.0 1.5-2.5 0.025 JIS SUS 445J2Others446 0.06 0.75 0.75 0.04 0.02 25.0-27.0 0.75-1.5 0.2-1.0 0.2 0.04 UNS S446260.01 0.4 0.4 0.02 0.02 25.0-27.5 0.75-1.5 0.05-0.2 0.2 0.015 0.5 UNS S446270.025 0.75 1.0 0.04 0.03 24.5-26.0 3.5-4.5 [0.2+4(C+N)]-0.80 0.035 3.5-4.5 UNS S446350.03 1.0 1.0 0.04 0.03 25.0-28.0 3.0-4.0 6x(C+N)-1.0 0.04 1.0-3.5 UNS S446600.01 0.4 0.4 0.03 0.02 25.0-27.5 0.75-1.5 0.015 0.5 JIS SUS XM27447 0.01 0.2 0.3 0.025 0.02 28.0-30.0 3.5-4.2 0.15 0.02 0.15 (C+N) 0.025 UNS S447000.03 1.0 1.0 0.04 0.03 28.0-30.0 3.6-4.2 6x(C+N)-1.0 0.045 1.0 UNS S447350.025 1.0 1.0 0.03 0.01 28.0-30.0 3.5-4.5 [4x(C+N)+0.15]-0.8 0.045 EN 1.45920.01 0.4 0.4 0.03 0.02 28.5-32.0 1.5-2.5 0.015 JIS SUS 447J1448 0.01 0.2 0.3 0.025 0.02 28.0-30.0 3.5-4.2 0.15 0.02 2-2.5 (C+N) 0.025 UNS S4480061

Impressive use of ferriticwelded tubes in a powerstation condenser.62

AppendicesSurface finishesSurface finishing treatments applied to stainless steels can take many forms.The main finishes are described below. Ferritic surface finishes are the same asthose for austenitic and other grades.Description ASTM EN 10088-2 NotesHot rolled 1 1E/1DCold rolled 2D 2DCold rolled 2B 2BBright Annealed BA 2RA comparatively rough, dull surface produced by hot rolling tothe specified thickness, followed by annealing and descaling.A dull, cold rolled finish produced by cold rolling to thespecified thickness, followed by annealing and descaling.May also be achieved by a final light pass on dull rolls.A bright, cold rolled finish commonly produced in the same way asNo. 2D finish, except that the annealed and descaled sheet receivesa final cold roll pass on polished rolls. This is a general-purposecold rolled finish and is more readily polished than No. 1 or No. 2D.BA finish produced by performing bright annealing in an inertatmosphere after cold rolling. Smoother and brighter than No. 2B.Brushed ordull polishedNo. 41J/2JA general-purpose bright polished finish obtained by finishingwith a 120-150 mesh abrasive, following initial grinding withcoarser abrasives.Satin polished(matt)No. 61K/2KA soft satin finish having lower reflectivity than brushed(or dull polished) finish. It is produced by a Tampico brush.Bright polished(mirror)No. 81P/2PThe most reflective finish commonly produced. It is obtained bypolishing with successively finer abrasives then buffing with a veryfine buffing compound. The surface is essentially free of grit linescaused by preliminary grinding operations.Electropolishedsurfaces- -This surface is produced by electrolytic attack. This electrochemicalprocess improves the surface finish by removing peaks of surfaceirregularity.(NB: the above table is not official and should be used only as a guide)2D 2B BA no. 4 no.663

AppendicesReferencesBucher, L., P.-O. Santacreu, et al. “Elasto-ViscoplasticBehaviour of Ferritic Stainless Steel AISI 441-EN 1.4509 fromroom temperature to 850°C.” Journal of ASTM International(JAI) Vol. 3, Issue 7 (2006). Also: Fatigue and Fracture Mechanics(symposium), Vol. 35.Cunat, Pierre-Jean. “Working with Stainless Steels” Paris:SIRPE, 1998.Fedosseev, A, and D. Raabe. “Application of the method ofsuperposition of harmonic currents for the simulation ofinhomogeneous deformation during hot rolling of FeCr.” ScriptaMetall. Mater Vol. 30 (1994): 1-6.Gümpel, P., N. Arlt, et al. “Simulation des Korrosionsverhaltensvon nichtrostenden Stählen in PKW-Abgasanlagen.“Automobiltechnische Zeitschrift (ATZ) No. 4 (2004):350-356.Huh, M.-Y., J.-H. Lee, et al.“Effect of Through-ThicknessMacro and Micro-Texture Gradients on Ridging of 17%CrFerritic Stainless Steel Sheet.” Steel Research Vol. 76,No. 11 (2005): 797-806.Kim, D. S., J. H. Park, et al.“Improvement of Cleanliness of16%Cr-containing Ferritic Stainless Steel in AOD Processes”,La Revue de Metallurgie No. 4, Paris (2004): 291-299.Kim, K, Y. Kim, et al.“POSCO’s development of Ferritic StainlessSteel.” The Second Baosteel Biennial Academic Conference Vol. 3,Shanghai, China (2006).Lee, S.-B., M.-C. Jung, et al. “Effect of Niobium on NitrogenSolubility in High Chromium Steel.” ISIJ InternationalVol. 42 (2002): 603-608.Lee, S.-B., J.-H. Choi, et al.“Aluminum Deoxidation Equilibriumin Liquid Fe-16 Pct Cr Alloy.” Metallurgical and MaterialsTransactions B, Vol. 36B (2005): 414-416.Miyazaki, A., J. Hirasawa, et al. “Development of High Heat-Resistant Ferritic Stainless Steel with High Formability, RMH-1, for Automotive Exhaust Manifolds.” Kawasaki Steel TechnicalReport No. 48 (2003): 328.Miyazaki, A., Takao, et al.“Effect of Nb on the Proof Strengthof Ferritic Stainless Steels at Elevated Temperatures.”ISIJ International Vol. 42, No. 8 (2002): 916-920.Murayama, M, N. Makiishi, et al. “Nano-scale chemical analysisof passivated surface layer on stainless steels.” CorrosionScience Vol. 48 (2006): 1307-1308.Park, J. H., D. S. Kim, et al.“Inclusion Control of Fe-16%CrStainless Steel Melts by Aluminum Deoxidation and CalciumTreatment.” AIST Transactions in Iron & Steel Technology MagazineVol. 4, No. 1 (2007): 137-144.Park, S. H., K.Y. Kim, et al.“Evolution of Microstructure andTexture Associated with Ridging in Ferritic Stainless Steels.”ICOTOM 13, Seoul, Korea (2002): 1335.Park, S. H., K. Y. Kim, et al.“Investigation of Microstructureand Texture Evolution in Ferritic Stainless Steels,ISIJ International Vol.42, No.1 (2002): 100.Park, S. H., K. Y. Kim, et al.“Effect of Annealing Process on theMicrostructure and Texture Evolution in Type 430 StainlessSteel.” Journal of the Korean Institute. of Metals & MaterialsVol.39, No. 8 (2001): 883.Park, S. H., K. Y. Kim, et al. “Effect of annealing process onthe microstructure and texture evolution in Fe-16%Cr ferriticstainless steel.” Rex & GG Aachen, Germany (2001): 1203.Park, S. H., K. Y. Kim, et al. “Effect of initial orientation andaustenitic phase on the formation of deformation band andrecrystallization behavior in hot rolled ferritic stainless steels.”THERMEC 2000, Las Vegas, USA (2000): 163.Raabe, D. “Experimental investigation and simulation ofcrystallographic rolling textures of Fe-11wt.% Cr.” MaterialsScience and Technology No. 11 (1995): 985-993.Raabe, D. “On the influence of the Chromium content on theevolution of rolling textures in ferritic stainless steels.” Journalof Materials Science No. 31 (1996): 3839-3845.64

Raabe, D. “Metallurgical reasons and mechanical consequencesof incomplete recrystallization.” Stahl und Eisen No. 120 (2000):73–78.Raabe, D, and K. Lücke. “Influence of particles on recrystallizationtextures of ferritic stainless steels.” Steel Research No. 63(1992): 457-464.Raabe, D, and K. Lücke. “Textures of ferritic stainless steels.”Materials Science and Technology No. 9 (1993): 302-312.Santacreu, P.-O., L. Bucher, et al. “Thermomechanical fatigueof stainless steels for automotive exhaust systems.” La Revuede Métallurgie No. 1, Paris (Jan. 2006): 37-42.Santacreu, P.-O., O. Cleizergues, et al. “Design of stainlesssteel automotive exhaust manifolds.”La Revue de MétallurgieNos. 7-8, Paris (July-Aug. 2004): 615-620. Also: JSAE Paper No.20037127 (2003).Schmitt, J.-H., F. Chassagne, et al. “Some Recent Trendsin Niobium Ferritic Stainless Steels”. Proceedings of thesymposium Recent Advances of Niobium Containing Materials inEurope, Düsseldorf (20 May 2005): 137.Sinclair, C.W., J.-D. Mithieux, et al. “Recrystallization ofStabilized Ferritic Stainless Steel Sheet”, Metallurgical andMaterials Transactions A, Vol. 36A (Nov. 2005): 3205.Van Hecke, Benoît “The Forming Potential of Stainless Steel”Materials and Applications Series Vol. 8, Euro Inox (2006).Toscan, F, A. Galerie, et al. “Relations between Oxidation Kineticsand Chromium Diffusion in Stainless Steels.” Materials ScienceForum Vols. 461-464 (2004): 45-52. Online at www.scientific.net.Yazawa, Y., Y. Kato, et al.“Development of Ferritic Stainless Steelwith Excellent Deep Drawability for Automotive Fuel tanks.”Review of Automotive Engineering Vol. 26 (2005): 59.Yazawa, Y., M. Muraki, et al. “Effect of Chromium Content onRelationship Between r-value and {111} RecrystallizationTexture in Ferritic Steel.” ISIJ International Vol. 43, No. 10 (2003):1647-1651.Yazawa, Y., Y. Ozaki, et al. “Development of ferritic stainless steelsheets with excellent deep drawability by {111} recrystallizationtexture control.” JSAE Review No. 24 (2003): 483.Sinclair, C. W., and J.-D. Mithieux, “Coupling recrystallizationand texture to the mechanical properties of ferritic stainlesssteel sheet.” Proceedings of 2nd International Conferenceon Recrystallization & Grain Growth, Annecy, France(30 Aug.–3 Sept. 2004): 317.65

AppendicesList of membersCompany membersAcciaierie ValbrunaAcerinox S.A.Acesita S.A.Aichi Steel CorporationArcelor MittalBaoshan Iron and Steel Co. (Stainless Steel Branch)Cogne Acciai Speciali S.p.A.Columbus Stainless (Pty) LtdDaido Steel Co. Ltd.Deutsche Edelstahlwerke GmbHHyundai Steel CompanyIndusteelJFE Steel CorporationJindal Stainless Ltd.JSC DneprospetsstalNingbo Baoxin Stainless Steel Co., Ltd.Nippon Kinzoku Co., Ltd.Nippon Metal Industry Co. Ltd.Nippon Steel and Sumikin StainlessNippon Yakin Kogyo Co., Ltd.Nisshin Steel Co., Ltd.North American StainlessOutokumpu OyjPanchmahal Steel Limited (PSL)POSCOPOSCO Specialty Steel Co., Ltd.Shanghai Krupp Stainless (SKS)SIJ - Slovenska industrija jekla d.d./Slovenian Steel GroupSteel Authority of India Ltd. (SAIL)Sumitomo Metal Industries, Ltd.Taiyuan Iron and Steel (Group) Co. Ltd. (TISCO)Takasago Tekko K.K.Tang Eng Iron Works Co. Ltd.Thainox Stainless Public Company LimitedThyssenKrupp Acciai Speciali Terni S.p.A.ThyssenKrupp Mexinox S.A. de C.V.ThyssenKrupp Nirosta GmbHUgine & ALZUgitech S.A.Viraj GroupWalsin Lihwa CorporationYieh United Steel Corporation (YUSCO)Zhangjiagang Pohang Stainless Steel Co. Ltd. (ZPSS)Affiliated membersAustralian Stainless Steel Development Association(ASSDA)British Stainless Steel Association (BSSA)CedinoxCENDICentro InoxEdelstahl-Vereinigung e.V.Euro InoxEUROFERInstitut de Développement de l’Inox (ID Inox)Informationsstelle Edelstahl Rostfrei (ISER)Indian Stainless Steel Development Association (ISSDA)Japan Stainless Steel Association (JSSA)JernkontoretKorea Iron and Steel Association (KOSA)New Zealand Stainless Steels Development Association(NZSSDA)Nucleo InoxSouthern Africa Stainless Steel Development Association(SASSDA)Special Steel and Alloys Consumers and SuppliersAssociation (USSA)Specialty Steel Industry of North America (SSINA)Stainless Steel Council of China Specialist Steel EnterprisesAssociation (CSSC)Swiss InoxTaiwan Steel and Iron Industries Association (TSIIA)Thai Stainless Steel Development Association (TSSDA)Union de Empresas Siderúrgicas (UNESID)66

AppendicesAcknowledgementsISSF is grateful to Friedriche Teroerde (ICDA) for writing theForeword to this brochure and to Philippe Richard (ArcelorMittal Stainless, France), who coordinated a working groupconsisting of Jacques Charles (Ugine & Alz , France), Peir-Teh Huang (Yusco, Taiwan), Kwangyuk Kim (Posco, SouthSouth Korea), Jochen Krautschick (ThyssenKrupp Nirosta,Germany), Juan Antonio Simon (Acerinox, Spain) andHideaki Yamashita (JFE, Japan). Thanks also go to BenoîtVan Hecke (Euro-Inox, Belgium) for checking the text and toPaul Snelgrove, freelance consultant and English-languagewriter (Paris, France), for his invaluable help in preparingthe brochure.Thanks are also due to de blauwe peer (Ghent, Belgium)for design and production, to MBCOM (Paris, France)for designing the cover and to Stevens Creative Printing,Merelbeke, Belgium) for printing.Photo creditsISSF wishes to thank the companies and individuals whohave contributed photographs to this publication. In thosecases where the original source of a photograph used is notknown, ISSF extends its apologies to the copyright owner.Front cover: MBCOM, Paris, France; p. 2-3: Ugine & Alz (Arcelor MittalGroup), France; p. 4: Columbus Stainless [Pty] Ltd, S. Africa; p. 5: Acesita(Arcelor Mittal Group), Brazil; p. 7: Lincat Limited, Lincoln, UK; p. 8: ISSFChina, PRC; p. 9 (tl): BSH Bosch und Siemens Hausgerate Gmbh, Munich,Germany; p. 9 (bl): Whirlpool Corporation, Cassinetta di Biandronno, Italy;p. 9 (r): Groupe SEB, Rumilly, France; p. 10: Acesita (Arcelor Mittal Group),Brazil; p. 11 (tl): IKEA, Aelmhult, Sweden; p. 11 (bl): Yiu Heng InternationalCompany Limited, Macao; p. 11 (r): Takara Standard Corporation, Japan;p. 12 (t): Acesita (Arcelor Mittal Group), Brazil; p. 12 (b): Tramontina, São Paulo,Brazil; p. 13 (l): Lincat Limited, Lincoln, UK; p. 13 (r): South Korea Iron & SteelAssociation (KOSA), Seoul, S. Korea; p. 14: POSCO, Pohang, S. Korea; p. 15(l & c): Ugine & Alz (Arcelor Mittal Group), France; p. 15 (tr): Suncue CompanyLtd. and Yieh United Steel Corp. (YUSCO), Taiwan; p. 15 (br): Japan StainlessSteel Association (JSSA), Tokyo, Japan; p. 16 (l): South Africa Stainless SteelDevelopment Association (SASSDA), Rivonia, South Africa; p. 16 (r): Acesita(Arcelor Mittal Group), Brazil; p. 17: Acesita (Arcelor Mittal Group), Brazil;p. 18 (l): Ugine & Alz (Arcelor Mittal Group), France; p. 18 (tr): Mac BrothersCatering Equipment, Cape Town, South Africa; p. 18 (br): Centro Inox andThyssenKrupp Acciai Speciali Terni S.p.A., Italy; p. 19: Acesita (Arcelor MittalGroup), Brazil; p. 20 (t): BSH Bosch und Siemens Hausgerate Gmbh, Munich,Germany; p. 20 (b): Faurecia, Nanterre, France; p. 21 (l): Valtimet, Boulogne-Billancourt, France; p. 21 (c): Ugine & Alz (Arcelor Mittal Group), France;p. 21 (r): Acesita (Arcelor Mittal Group), Brazil; p. 22 (l): Sander Inox andNucleo Inox, Brazil; p. 22 (r): Ompagrill and Centro Inox, Italy; p. 23: BSHBosch und Siemens Hausgerate Gmbh, Munich, Germany; p. 24 (tl & tr):Japan Stainless Steel Association (JSSA), Tokyo, Japan; p. 24 (br): ColumbusStainless [Pty] Ltd, S. Africa; p. 25 (l): South Korea Iron & Steel Association(KOSA), Seoul, S. Korea; p. 25 (tc): Ugine & Alz (Arcelor Mittal Group), France;p. 25 (tr): Faurecia, Nanterre, France; p. 26 (t): Group SEB, Rumilly, France;p. 26 (b): LG Electronics, S. Korea; p. 27 (l): Columbus Stainless [Pty] Ltd,S. Africa; p. 27 (r): Japan Stainless Steel Association (JSSA), Tokyo, Japan;p. 28 (l): BSH Bosch und Siemens Hausgerate Gmbh, Munich, Germany;p. 28 (r): South Korea Iron & Steel Association (KOSA), Seoul, S. Korea;p. 29: Taiyuan Iron & Steel (Group) Company Ltd. (TISCO), Taiyuan, PRC;p. 30 (t): ISSF China, PRC; p. 30 (b): Qingdao Haier International Trading Co.Ltd., PRC; p. 31 (l): SunTank, Pretoria, S. Africa; p. 31 (r): Japan StainlessSteel Association (JSSA), Tokyo, Japan; p. 32 (box): POSCO, Pohang, S. Korea;p. 33 (all): Ugine & Alz (Arcelor Mittal Group), France; p. 34 (l): Centro Inox,Italy; p. 34 (tr): Faurecia, Nanterre, France; p. 34 (b): all 4 photos Ugine & Alz(Arcelor Mittal Group), France; p. 35: Acesita (Arcelor Mittal Group), Brazil;p. 36 (t): ThyssenKrupp Nirosta GmbH, Krefeld, Germany; p. 36 (b): MacadamsBaking Systems (Pty) Ltd, Cape Town, S. Africa; p. 37 (l): Faurecia, Nanterre,France; p. 37 (r): Ugine & Alz (Arcelor Mittal Group), France; p. 38 (l):Faurecia, Nanterre, France; p. 38 (r): Ugine & Alz (Arcelor Mittal Group),France; p. 39 (l): SunTank, Pretoria, S. Africa; p. 39 (tr): Acesita (ArcelorMittal Group), Brazil; p. 39 (br): Solaris Bus & Coach Co., Poland; p. 40 (l):Brandt Edelstahldach GmbH, Cologne, Germany; p. 40 (r): Ugine & Alz (ArcelorMittal Group), France; p. 41 (tr): Ugine & Alz (Arcelor Mittal Group), France;p. 41 (br): ThyssenKrupp Nirosta GmbH, Krefeld, Germany; p. 42 (tl): Willemde Roover, Ghent, Belgium; p. 42 (bl): Faurecia, Nanterre, France; p. 42 (tr):Centro Inox, Milan, Italy; p. 42 (br): Ugine & Alz (Arcelor Mittal Group), France;p. 43: Hanjin, S. Korea; p. 44 (t): Groupe SEB, Rumilly, France; p. 44 (b):Lincat Limited, Lincoln, UK; p. 58: ThyssenKrupp Nirosta GmbH, Krefeld,Germany; p. 62: Valtimet, Boulogne-Billancourt, France; p. 63: POSCO, Pohang,S. Korea.DisclaimerEvery effort has been made to ensure that the information presented in this publication is technically correct. However, thereader is advised that the material contained herein is intended for general information purposes only. ISSF, its members,staff and consultants specifically disclaim any liability or responsibility for loss, damage or injury resulting from the use ofthe information contained in this publication (in printed, electronic or other formats).Date of publication April 2007 - Copyright - ISBN 2-930069-51-167